mellored
Legend
Or use maneuvers.+1.
That's the real trick, isn't it? There would have to be enough flexibility built into the class to allow many different variations. I get the impression that the "Noble" class by Moonsong (available in EN5ider) goes a lot of the way there, and it does so by starting with a stripped-down base chassis for the class, with most of the variation appearing in the different subclasses. That seems to be the best approach, at least as far as the challenge of appealing to many different desires goes.
The reason why you can have an illusionist, conjurer, and an evoker in the same class is you can select spells a-la-cart.
The wizard base-class is literally
1: You cast spells. More often and bigger spells as you level.
2: You cast more spells.
18: You cast a selected low level spell at-will.
20: You cast some spells once per short rest.
From there you can build support, disabling, utility, illusions, blasting, or whatever combination you feel like.
Now imagine a martial class that way. With a simple base class, and a-la-cart maneuvers.
1: You do a maneuver. Bigger maneuvers as you level.
2: You learn a passive maneuver. More as you level.
18: You can do a selected low level maneuver each turn for free.
20: One per short rest, you can do 2 maneuvers at once.
Maneuvers include sneak attack, multi-attack, cunning action, second wind, defensive maneuvers, commander's strike, rally, rage, etc...
Passive maneuvers would be stuff like blind sight, slippery mind, fighting style, favored enemy, danger sense, unarmed defense, ect...
You could easily have fighter, rogue, warlord, (spell less) ranger, and barbarian, all in the same class. Possibly even monk.