Level disparities between classes.

[Roxxy]

All the players in a D&D/PF game should of course be the same character level or close to it, regardless of class. No reason that needs to apply to NPCs with character class levels, though. The average level of an NPC fighter within a setting need not be the same as the average level of an NPC barbarian. In my campaign setting, this is most notable with spellcasters. It's an Eberronish setting, where low powered arcane magic is common and is technology, but high powered arcane magic is rare. The average level for an NPC arcane spellcaster or alchemist is 2. For martials, however, it is 4. For divine/psychic spellcasters and witches, it is 6. None of this applies to player characters, of course, because they are not average people, but when looking at the roles of the classes within the setting, one sees a very clear power disparity between the divine/psychic classes (and witches) and the arcane classes. A PC witch and a PC wizard are equals in power, but an average witch trumps an average wizard handily. This inequality factors in to how witches are viewed within the campaign setting quite a bit. Since becoming a witch, divine, or psychic spellcaster is very difficult and requires collusion with feared spiritual or extraplanar entities, there aren't a lot of these casters in the setting, yet they are very powerful compared to the arcane casters. This means they scare people and have little societal acceptance, even though arcane magic is ubiquitous and forms the main technological base of the world. It also doesn't hurt that I took away the ability for arcane casters to summon outsiders (who are usally bad news) or create undead. Need the divine/psychic/witch people for that, but people are really scared of that stuff.

Does anyone else use a disparity between average class levels such as this to refine the flavor of a setting?

[Khedrac]

All the players in a D&D/PF game should of course be the same character level or close to it, regardless of class

Well, seeing as you posted this in the general roleplaying forum I will disagree with your opening statement.

Yes it is true for D&D 3E, 3.5 and PF, but it is not true for D&D (B/E/C/M/I), OD&D or AD&D...
These versions of D&D specifically had the different classes require different amounts of XP to reach levels which pretty much mandated a level spread.
OK - I suppose I still have to give you "close" :)

As for how I balance for flavour in a setting, I make NPCs the level I need them to be, but I balance the commonality of classes to give flavour.

[Yora]

The way I run campaigns it doesn't really matter, since the players are always going to see only a tiny fraction of people in the world and global or even regional averages don't become visible in any way.

[Broken Crown]

Mostly I do this to reinforce the theme of a particular location. Feudal society? More mounted, armoured fighters. Lands bordering on wilderness? More rangers. The patron deities of a region will have more and higher-level clerics than the less-worshipped gods. Areas with an exciting recent history will have more heroic high-level NPCs of an older generation than places that have been staid and boring for a while.

[Jormengand]

I usually use quantity, rather than quality, for this. The idea that if you're from a society which doesn't endorse what you do then you must be bad at what you do is not one which I want to enforce. The idea that if you're from a society that doesn't endorse what you do then few other people will do it is true and makes sense. At most, they will have fewer resources at their disposal (wizards would only be able to access spells that they learned, not ones that they copied up), rather than level, optimisation level, or general competence.

[Honest Tiefling]

I usually use quantity, rather than quality, for this. The idea that if you're from a society which doesn't endorse what you do then you must be bad at what you do is not one which I want to enforce. The idea that if you're from a society that doesn't endorse what you do then few other people will do it is true and makes sense. At most, they will have fewer resources at their disposal (wizards would only be able to access spells that they learned, not ones that they copied up), rather than level, optimisation level, or general competence.

While I would agree with this, I would imagine, given the description of the setting, that being a psychic/witch is a bit of a sink or swim situation. I assume that wizards might outnumber witches, but witches have better access to power that weeds out the weak pretty quickly, leaving only the strong. Of course, this does depend on how these dangerous spellcasters gain power. If all a wizard needs to do is study, has access to a center of learning and a mentor, while the witch needs to perform great deeds to appease these outsiders, I...Would kinda expect the wizards to get the upper hand in many cases, really.

I would also think that in many settings, people lack information about other's real powers and abilities, so I am going to take the lazy route and never define it. Many people might not know the real difference between the two types of casting, and why not pretend to be the other, to either intimidate those around you or to lull your enemies into a false sense of security? How many of these people will players really remember or be able to accurately judge? Rumors are nasty, unreliable things, really.

[goto124]

What does 'witch' mean in this context? Warlock who made a deal with the devil?

[Roxxy]

What does 'witch' mean in this context? Warlock who made a deal with the devil?

Pathfinder has a witch base class.

[Mechalich]

The core DMG world-building rules for 3.5 assume that there will be a disparity between average level between classes and that fighters and rogues are the most abundant classes with the highest average level, though I'm not sure any specific justification was ever provided for this.

I would assume that the implicit justification is that it is both somehow 'easier' to become a fighter or rogue and that you can do so at a younger age, that the expenses required to become a trained spellcaster limit the ability to acquire that training to the upper classes while anyone can pick up a sword, and that advancement as a spellcaster is more ability score-dependent.

Of course, this doesn't really seem like it should hold up. Since a high-level prepared spellcaster can easily become effectively immortal, they really ought to proliferate in a way high-level martials really cannot due to growing old. So unless all the wizards are periodically leaving to live on other planes (possible) a setting ought to accumulate them across the centuries.