Desdichado
Hero
As long as you fix that quote to refer to your game and not imply that any of that is inherent in D&D itself, sounds good enough.Id say
"Ok, thats a great character concept, and would be brilliant in a different game system or campaign, where you can use this flaw. Savage worlds for example. As it is where playing D&D where the party are heroes and dont have such flaws manifest. More importnatly this is a team game. we have gathered here to play as a party. Good as this concept is it doesnt fit with what we are trying to create with this campaign."