I think sometimes defini
I don't think we need a fighter of the complexity of the 0e or 3e Fighter or Thief.
"Simple" I think will always be measured in comparison to other examples, we don't need something that is "absolutely simple".
Maybe there are players that really only want an auto-pilot character
But getting rid of the 5E spellcasting system seems the requirement for simple, because it really is a lot of complexity:
- Spell descriptions are already a complex system: All that the boiler plate that defines the basics of the spell, like range, action, school, level, up-cast benefits, and than the actual spell description which has its own rules.
- The way you learn and prepare spells - especially since for some classes, these are seperate things - has its own complexity, that they are similar but different makes it worse.
- Casting spells involves managing multiple similar but discrete resources in the form of spell slots.
I would definitely settle for "has at least a subclass that is as simple as a spell-less fighter or rogue subclass." This removes a lot of complex subsystems, but of couse it will still leave
some subsystems to manage. The existing ighter or rogue however don't need to be optimzied to our simple distinction, just the first thing to compare toward.
That's still not as simple as a 0e Fighter. It might be as simple as some 3E Fighters (because the Fighter bonus feats in 3E did almost require you to get involved in the 3E complex subsystems like Tripping, Disarming, Sundering, Power Attack, Attacks of Opportunities, Grappling and so on, or at least require you to look at them before you discard them for "simple" feats...)
Ideally the choices at each level should be clear and limited, but there should still be some choices over the levels (maybe in addition to choices provided by subclasses). I think part of that is about presentation - instead of giving a lot of options you have to consider every round, spell out what each feature or ability is for more clearly. Instead of saying choosing 2 spells from a list of dozens or more, you get a choice like. "You get a magic ability to help you move on the battlefield, these are your
n options, where
n might somtimes be the number of subclasses."
Alterantively, it might be "You know that ability that helps you get around the battlefield? This subclass lets you leave behind a wall of fire in your tracks, and that one lets you teleport instead, and this one lets you take a friend with you."
Particularly in combat, there shoud also be still some class-specific choices left, but they could probably be more siloed. A spell can be anything - attack, heal, control, buff, or utility for travel or information gathering or something else. And it could be any level and any type of action. This can often lead to analysis paralysis.
To counter this, I think you need to define the options in some sort of silos that you can distinguish.
Say, you explicitely have a magic action that either attacks, heals, controls, buffs or has some utility (like for travel, exploration). Each subclass might add its unique features for that (and maybe not all offer every option). But you still have different options each round, and must decide which one to take. Analysis Paralysis isn't gone entirely, but the space of options is smaller, and more straightforward, the biggest thing is to figure out if you rather want to attack, control, heal, buff or check if your utilities can help.
I'd still say layering a simple mana/force/focus/maneuver/resource point system on top is okay, even if that is additional complexity.
The goal would be that at least some, if not all, subclassses keep that pretty straightforward, like simply boosting the available actions. So you can at least say "I hit it, but with emphasis" and have a bit of tactical choices. "Okay, now that I have advantage, I boost my attack's damage", "now that I have disadvantage, I rather provide a buff to an ally". "now that my ally is reduced to 0 hit points, I provide him with a bigger heal"
