The 4e combat roles are much too broad. They needlessly restrict and reflavor creativity and distinctive professions and tactics.
I...don't understand how these two sentences make sense together. If it is broad, and therefore interpretable in very different ways that are still consistent with the meaning, how is that "needlessly restrict[ive]"?
What they call the controller, for example, covers area of effect damage and other distinct things needlessly. There should be recognition and accessibility for each, and different versions of each.
Well, firstly, I'll note that area-effect damage is one of the things not
strictly tied to any particular role, even in the abstract. Sorcerers get quite a bit of it, for example; Monks technically do not get "AoE" damage, usually, but their movement-with-attack features (called "Full Disciplines") mean they usually deal damage to multiple foes a round, effectively equivalent. And most Defenders can pick up powers that allow marking a group or an area at once (usually centered on them); while they cannot usually
maintain those marks indefinitely, they're often worth a round of punishment, and the ability which does the mark-ing usually deals some damage too.
Secondly, there's at least one, and if you're flexible two, classes that do "single-target" control, as I understand it. The Seeker, though often considered an underpowered class, does best when controlling individual foes, as their control effects are delivered via magic-enhanced archery. Then, if you're flexible, the standard 4e Warlock can, with careful building, be a very competent single-target controller, inflicting debilitating status effects on whichever enemy is currently affected by their Warlock Curse. (Disclaimer: Never played either one, so I may be misremembering some things.)
So...yeah. Again, I don't think 4e's roles are
nearly as prescriptive as you're saying. They are broad, not because you ABSOLUTELY MUST DEFINITELY meet EVERY SINGLE criterion inside them in order to succeed. Instead, they're more like chunks of...even "design philosophy" seems a little too narrow. They're guidelines, or perhaps "priorities lists"--you don't have to meet all of them, and there can be many ways to meet them that are still successful. Suggestions for appropriate behavior, depending on what the designers want a class to be able to do well before the player applies any amount of tinkering, customization, tactics, teamwork, etc.
I feel the game has bluffing down well enough, but diplomacy should be distinct from charming. Diplomacy is a negotiation between parties who have a dispute or who need to reach an agreement. Charming is what is done to make a friend, win a vote, or to initiate a romance. Diplomacy requires different skills, and most importantly to distinguish it from charming, "leverage". The diplomat has "a hand", which he plays. The charmer can just put his cards on the table.
Alright. I guess I feel like the difference you're drawing between those social skills is excessively narrow--and, IMO, restrictive--for my tastes. The negotiator is trying to convince a particular person to have a particular opinion; the charmer is trying to convince a particular person to have a particular opinion
of them. Both involve persuading a person to think something particular about a thing. I see this as analogous to the "ranged damage/melee damage" dichotomy. A class that a designer wishes to have baseline solid damage will be given a feature that enables this. That feature might focus on melee damage, ranged damage, or both without particular focus. (For example: in 5e, Sneak Attack is agnostic, capable of riding on both melee and ranged attacks; while the various Paladin smite spells, IIRC, are melee attack specific, and several Ranger damage spells are ranged-only.)
Also, I think we're just gonna have to agree to disagree, about the "most characters should be competent at most things." I see D&D as inherently a cooperative endeavor, and feel that the game should encourage that cooperation. Teamwork should, IMO, be
required, not just useful. No character class, IMO, should be able to do absolutely everything, and no individual character should be good even at a majority of things all at once. (I'm skeptical of characters that can be good at many things which change from session to session--that's where 3e casters became horrible monsters--but I'm open to the possibility that 3e's flaws are not inherent to that style of character.)
Characters that are good at (essentially) everything all the time are boring to me--and if only some party members can achieve this, they overshadow the others (eventually). Characters that can be made to be good at anything, but have no natural capacities, risk either becoming the former, or risk the "newbie trap" problem of the "character that can try everything, but succeeds at almost nothing." Hence, again, why I think roles are so useful: no matter how they're defined, they make the designers conscious of the places where a class isn't actually achieving anything meaningful and thus needs to be redesigned, while
also making them aware of classes that achieve everything (whether simultaneously or serially) and thus
also need to be redesigned.