Required reading:
It's considered common knowledge that having wide power variations among characters spells trouble for players. It doesn't just cause metagame issues, though. DMs often complain about not being able to challenge higher tier characters without steamrolling lower tier ones.
I've always been wary of both sides of the coin, however. Sufficiently mature players simply adequately role play being overshadowed and do not try to cause problems because of it. They have to have enough system mastery to understand that they are choosing to not be superman, of course. I often request higher constraints on any characters I build when I play.
DMs who complain about "fighter+monk+wizard+cleric" being incredibly lopsided often need to be taught to expect that sort of thing when they come to us looking for help. But the more I think about it, the more these sorts of DMs often need to be taught system mastery itself. I'm not sure I've seen a highly skilled DM that admits they still can't handle these sorts of things.
It makes me think that the above "problems" are simply system mastery problems, rather than that wide-ranges in power make a DMs job unplayable. For instance DMs found to complain about the above often are trying to do no-no's like pit single adversaries against whole parties. It seems to me that with enough DMing skill, and players who can rise to the challenge, that mook-clearing can fun times for the lowest tiers along with the highest ones.
A more concrete example was in Age of Ultron, where the party tried to secure a core against an onslaught of robots trying to touch it. If they failed, the core would wreck havoc. High-powered characters fought alongside low-tiered ones without much of a "wait a minute" moment, even when I was actively looking for one. Sure, the more powerful characters cleared
more mooks, but at a certain point the numbers differences don't matter (either to the players or for the sake of the story).
Indeed movies like the Avengers are totally fine splitting up role-playing time and action time whilst giving higher time in the spotlight to the less powerful characters. It seems like players would enjoy that too: "How much do you want to role play? Lots or little? Build to suit." Personally, I love to role play as a DM, but dislike it as a character. I'd love to be given the choice.
tl;dr look at how the line-up
just plain works:
It gets even more wildly variant at the end, and I have no doubt that it'll still be fine.
One of the best players that I DM'd was a core-only monk. He took the toughness feat and it saved his life. Yes, he planned to retrain it out, but still. Who takes the toughness feat? He kept being surprisingly useful, but he never was in danger of overshadowing the other players. I was very glad to have him as a player. He role played: he accepted quests, he talked to NPCs, he put two and two together, he helped calm down other players.
It kind of reminds me of when Hawkeye says that its just plain crazy that he's a guy with a bow and arrow against a thousand robots. But he's going to go out and do his job and not whine like the much higher-powered psychokenesis+suggestion girl.
