Character Concepts you wished would work in D&D?

[Man_Over_Game]

A few things I feel are missing:

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3. Martial class focused on Area Control. Open Hand monk is the closest one thus far, but I imagine it to be more AOE control rather than single target control spread out through multiple attacks.

I feel like this is already covered with the Cavalier Fighter (using one of your extra feats for PAM) or Conquest Paladin.

Don't get me wrong, I'm a big advocate for more complex Martial options, I'm just not sure if 'AOE Control' is enough of an unfilled niche to be the only basis for a new subclass.

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But, these merely require choosing more class features, and they're mostly permanent until you gain a level. A hypothetical Binder essentially changes its subclass daily. Think about the Rogue replacing the first level of its subclass every day: one day the Rogue's a Thief, the other an Assassin, the next a Mastermind, then back to Thief. You can't change it until the next day, so you need to choose very carefully what's your focus for the entire day. Or, as a choice that reflects closely what you'd intend - the Barbarian's Totem Warrior. You're supposed to mix and match the options of your Totems as you gain levels: you don't have to go full Bear, or full Eagle, or full Tiger. You can, theoretically, mix and match stuff. The Totem Warrior's options are still locked in a way - this would make your options change daily. And they wouldn't be just like the Totem Warrior - they'd be closer to domains, since they define your bonus proficiencies and some of its traits.

I understand mix and match can be fun - it's half of the fun for those who like system mastery. But the system was designed towards simplicity: don't clutter the system with a lot of options. Right now, you can define which options don't work and which one work better, but the distance between optimization ceiling and floor is much, much smaller. This is the system's attractive, IMO. If you make a class whose entire purpose is redefining itself daily (with an ability check that essentially defines if you're going to have an extra flaw for the day or not), it'll be cool and interesting, but it'll be a nightmare for newbies who might find it cool, and will cause a reaction similar to the Truenamer (not exactly, since at least the mechanic would be solid and not broken, but in terms of feel because people will see the class needlessly complicated).

A long while back, me and some folks on the forum were looking into ways to make the Druid's Wildshape easier and more versatile. The solution we came up with was just a series of "chassis" and "modules" that you chose from.

For example, you could pick a Stout form, which had doubled HP and medium AC and speed, or a Hunter form with medium HP but doubled AC bonus and doubled speed.

Everything was based around ratios (x1 or x2), and the base values were based on your level. Halve your HP, speed and AC bonus if you chose a flying creature (so a Stout Flying creature would have x1 HP, x1/2 speed and x1/2 AC bonus).

I think something similar could be done to make a versatile shapeshifting mechanic without it being much rule keeping. You don't need special use to determine how much a grappling attack costs, as long as it functions the same as your Prone attack, or your Savage Attack (which is just an extra attack if the condition is met). Make the conditions for each benefit type to be incredibly simple and limited, and the end result will still be simple (but versatile).