Experiences with SRD variant classes.

[Marlowe]

Battle Sorceror. Domain Wizard. Thug. Sneaky Thug. Urban Ranger. Wildshape ranger. Urban Wildshape Ranger (is that even legal?). Racial Paragon classes. Spontaneous Clerics. Things like this.

Never played with any of these. Any experiences? Good? Bad? Ugly? Fun? Advice on how they play differently? How do they effect Tier placing?

Just from looking I imagine the Battle Sorceror would probably be down a Tier compared to the standard sorc, although it looks like a fun option. Sneak-attack Thug would be interesting but I can't imagine him doing anything that a Rogue/Swashbuckler with Daring Outlaw couldn't do better. A spontaneous Cleric would have some heartbreaking decisions to make, but again would make for a fun build.

Comments from those with thoughts or experience? Better yet, thoughts and experience?

[Acanous]

Domain Wizard is a game breaker.
Elven Generalist Domain Wizard, in particular.

[kardar233]

Sneak Attack Thug Fighter is a great entrance for sneaky+fighty classes.

Paladin of Tyranny is possibly my favourite base class.

[Rhaegar14]

One observation: Spontaneous Cleric is a good option, if you don't want Tier 1 characters in your campaign, to create a Tier 2 divine caster that can still benefit from the plethora of feats that run off Turn/Rebuke Undead. And I'm fairly certain that Spontaneous Druid is the only way you get a Tier 2 caster with the Druid spell list. XD

[Lonely Tylenol]

Battle Sorceror. Domain Wizard. Thug. Sneaky Thug. Urban Ranger. Wildshape ranger. Urban Wildshape Ranger (is that even legal?). Racial Paragon classes. Spontaneous Clerics. Things like this.

Never played with any of these. Any experiences? Good? Bad? Ugly? Fun? Advice on how they play differently? For do they effect Tier placing?

Just from looking I imagine the Battle Sorceror would probably be down a Tier compared to the standard sorc, although it looks like a fun option. Sneak-attack Thug would be interesting but I can't imagine him doing anything that a Rogue/Swashbuckler with Daring Outlaw couldn't do better. A spontaneous Cleric would have some heartbreaking decisions to make, but again would make for a fun build.

Comments from those with thoughts or experience? Better yet, thoughts and experience?

Of the UA variants:

Totem Barbarian makes Barbarian sorta fun in a sense that you can trade out features for other, more useful features for a specific character type (Bear and Wolf totems are useful for grappling and tripping builds, respectively), but few of them have any really good features, so the Jaguar totem (which is standard Barbarian) with perhaps some more useful ACFs is often advised. Worth mentioning, however, that the spirit totem and spirit totem manifestations from Complete Champion have some good options as well (hint: they have "Lion" in their name).

Bardic Sage and Divine Bard both split the Bard's casting into two attributes (Bardic Sage requires INT for spells known and Divine Bard requires WIS; both use CHA for everything else), and Bardic Sage trades a lot of extra stuff (a good save progression, bardic music capabilities) for a few spells known. Neither is really worth playing. Bardic Sage is basically Cloistered Cleric with some music abilities (but you'd really be better off with a Cloistered Cleric). Savage Bard, on the other hand, is good if you want a strong Fortitude save (it loses Reflex); you lose Speak Language, Decipher Script, and a few spells, but gain Survival and a lot MORE spells.

Cloistered Cleric is like a complete overhaul of the Cleric; loses BAB (drops to poor) and Hit Dice (drops to d6), but gains skills (6+INT), extra class skills (including all knowledge skills), another domain (Knowledge), extra spells on the spell list (remember: all Clerics can prepare any spell from their list, unless they're spontaneous), and Lore (AKA Bardic Knowledge). All told, this is the best thing that has ever happened to the Cleric, since it gains a large number of great benefits, and two small drawbacks that are completely replaced by Divine Power and other buffs anyway.

I also consider Druidic Avenger one of the best trade-offs in the game, but you have to remember two things to make this true:
1) Rage is a class feature, and, depending on your interpretation of the rules, can itself be traded for alternative class features. A level 1 Druid casting Shillelagh and going into Whirling Frenzy, for example, is a fearsome melee combatant, and so is a level 5 bear with Whirling Frenzy. (NOTE: I don't count on this actually working, because it's a level of cheese that I wouldn't be comfortable with in *my* game, and is dubious in most others, so I would pursue this at your own risk if you intend to play a Druidic Avenger. If your group is Chaos Shuffling feats, however, they probably have no objection to ACF chaining.)
2) Animal companion is two feats - Wild Cohort and Natural Bond - and a third, called Shared Fury, makes your animal companion better than he ever was. (Let's be honest; what else were you going to use those feats for, aside from, I suppose, Natural Spell?)
If you play E6, then Druidic Avenger is one of the best single-classed options in the game; it gets two uses of Rage (the same number as a Barbarian gets), plus all the Rage-enhancing feats that Barbarians get (since they simply require Rage as a class feature); wildshape at level 5; Natural Spell at level 6; and third-level Druid spells, which means that not only are they a one-man army, but they're an angry one-man army.

The Thug variant of Fighter, in and of itself, isn't that fantastic. The only thing that redeems it, actually, is that it comes for free with the Sneak Attack variant of Fighter (which has some niche applications).
Again, E6 players win big here: The Sneak Attack +2d6 of a Sneak Attack Fighter allows you to qualify for Daring Outlaw with Swashbuckler, but the levels between the two don't stack, so you get third-level Sneak Attack from Swashbuckler levels plus third-level Sneak Attack from SA Fighter levels, for a total of +4d6, which is better than you could have gotten from six levels of Rogue (or six levels of Rogue/Swash Daring Outlaw). You also get +6 BAB, which means a second iterative attack (and access to Improved Two-Weapon Fighting). There is literally no way that comes to mind to me to do Sneak Attacking better than that in E6.

The Monk fighting styles are... Interesting. Cobra Strike grants the Spring Attack chain of feats for free, but most of the Spring Attack chain is terrible (even with the extra +2 dodge bonus, Dodge is pretty horrendous; why couldn't it just apply to everyone?). Denying Stance and Hand and Foot each give... Three of the six bonus feats Monk gets anyway (not sure what they were thinking there), plus a minor bonus to a skill and a minor 6th-level ability (so if you were planning on picking those skills anyway, take the fighting style for free benefits). Invisible Eye is more or less terrible, Overwhelming Attack is a decent dip for charge/bull rush builds (but you're still trading benefits with the 2-level Fighter Dip, though they work well together I suppose), Passive Way is a good way for tripper builds to avoid needing 13 INT, Sleeping Tiger is good only as a two-level dip for high-DEX builds (Improved Sunder and Sneak Attack +1d6 are the 6th-level abilities, but Weapon Finesse and Improved Initiative are nothing to sneeze at), and the Undying Way is... What.

The Paladins of Freedom and Tyranny are both, in many ways, strictly superior to the Paladin of Honor; the Paladin of Freedom is immune to compulsion effects (and keeps Lay on Hands, for whatever that's worth), while a Paladin of Tyranny has Deadly Touch and Aura of Despair, the former of which synergizes very well with a two-level Paladin dip, and the latter of which synergizes well with every effect any member of your party has which offers a saving throw, including Deadly Touch.

Planar Ranger and Urban Ranger... ??? Seems like a minor buff to me if the campaign deals largely in planar or urban settings, but...?

Wilderness Rogues get Hide in Plain Sight and Camouflage added to their special abilities, which is cool, and the skill switch only harms social rogues significantly.

Battle Sorcerer seems like a very harsh debuff. The d8 Hit Dice, medium BAB, and light armor/limited martial weapon proficiency are nice, but knowing one fewer spell at every level is INCREDIBLY harsh at any level (and one fewer spell per day at every level is very harsh at low levels, too). You basically gain the spell progression of a Wilder. Still a solid option, I suppose, if you want a character that is vaguely martially proficient (you become a martial Bard with better spell selection and durability, but no class features), but if it were me, I'd go with the Stalward Sorcerer variant from Complete Mage, which gives 2 hit points per level and the same martial weapon proficiency (plus Weapon Focus on the weapon), but only loses a single spell at the highest level (the class features you gain are almost completely identical, but you keep more of your spellcasting in exchange for a little bit of martial proficiency). If I recall, the Battle Sorcerer and Stalwart Sorcerer can be stacked on top of each other for double the benefits and none of the losses; if I had to make a single-classed gish, this is probably still not your best option (Duskblades are less durable and cap out at a lower spell level, but get full BAB, useful class features, and a plethora of spells/day, and the PF Magus is the Wizard equivalent of this same thing), but it's... Better. Kind of like a divine Favored Soul. If you're multi-classing (or PrCing out), however, neither offers useful class features that a dip in Fighter or Paladin can't give you (and they give SO MUCH ELSE, too).

Domain Wizard is a straight improvement over the generalist wizard (literally; you're trading nothing but the ability to specialize in exchange for automatic access to all your domain spells and an extra spell/day at every level for those spells). The Elven Generalist Domain Wizard is well-known abuse of this.

As for the other class variants...

Crafty Hunter Barbarian is a strict debuff from regular Barbarian, as well as a strict debuff from Ranger;

Nature Bard synergizes well with Savage Bard, I suppose, but seems fit to rob it of all original class features to do so (making it Druid Lite);

Smite Cleric seems like a good idea for martial Clerics who are new to the game, but is in fact a HUGE trap, since Turn Undead is one of the greatest resource pools a Cleric has (thanks to a plethora of feats that burn Turn Undead uses, such as the Divine feats and Devotion feats, notably Travel Devotion and Divine Metamagic);

Why would anyone ever give up Wild Shape?!;

Sneak Attack Fighter has limited applications (a one-level dip in a Sneak Attack-heavy build, for example, or more levels in a full-BAB Sneak Attack build);

DR Monk is... Actually not terrible, but they're about equal in power, so you have to decide which is better for yourself;

Paladins giving up Turn Undead and other features for Favored Enemy makes me cry blood;

Wildshape Ranger is perhaps the biggest single buff any class has ever gotten as a variant (somebody will probably prove me wrong here, though);

Feat Rogue seems to be missing the point (and is only useful as a two-level dip);

Animal Companion Sorcerer/Wizard is a straight buff from familiar, and Natural Bond can keep it somewhat combat-relevant for the first little while (but unless you're playing a game that starts at low level and likely isn't going to make it to high level, you might want to trade your familiar for something else);

Fighter Feat Wizard is fantastic for Wizard dips. After all, if you're not going to get a lot (or any) use out of Scribe Scroll, why not trade it for Improved Initiative? You're not going to take five levels of Wizard anyway, so you're likely not going to suffer the loss of a metamagic or item creation feat.

[eclipsic]

I played an urban ranger variant in a city-based campaign, and it wasn't too bad. I play in a fairly low-op group, and the Urban Tracking feature came in handy many times when a more op'ed group would just use spells. Likewise, my animal companion (a small dog) was a decent common area spy when spells also would've worked better. The "organizations as a favored enemy" thing was useful, especially when actually fighting my favored enemy, be they halflings, dwarves, or whatever, but it wasn't overwhelmingly useful. I liked the feel of the urban ranger, though, and if I had been aware of Urban Soul (from RoD), I would've PrC'ed into that, also for the flavor.

All things considered, it's probably as useful in a strictly urban setting, and considerably less useful anywhere else, except that the urban ranger does get Hide in Plain Sight in all terrain, and not just natural terrain.

[DeAnno]

Spontaneous Clerics can be good (and more relaxed in terms of daily piloting) if they are high level enough to drink Domain Draughts (MiC 156) like water. In general its a decent option for any focused build, like an indomitable superhealbot.

[Amphetryon]

I had a Druidic Avenger shortly after the variant was published, and before most folks I knew were optimizing at all. The DM considered it somewhat overpowered on the theory that it removes one of the 'weaker now, stronger later' assumptions that were built into D&D's class and level structure. In other words, Rage made me a viable low-level combatant who didn't need to buff with any spells before wading into battle. YMMV.

[DigoDragon]

I like playing a Cloistered Cleric with the Trickery and Magic domains. They make a great "skillmonkey" character. :smallsmile: It got even better when the GM allowed me to replace the Bardic Knowledge ability with Bardic Knack from PHB2.

My wife played a really good spontanous-casting cleric once. With the right spell selections she was like an effective battle sorcerer with healing.