nute said:"Roleplaying" implies that the players get into the personality of their character, not just the stats. Phil the Bard woos the barmaid because he's an insatiable lothario, not because he has a 19 Charisma and expects to get XP for "acting in character". Bob the Ranger doesn't pick goblinoids as his favored enemy because the bonuses allow him to slay CR 1/2 goblins by the dozens, they're his favored enemy because a band of hobgoblins razed his humble farming village to the ground. That's roleplaying.
The first problem is that "characters traits" (what you call "personality") aren't part of the D&D game. The second problem is that it's very difficult to add them and make them relevant because the game is "challenge-based" (classes + level).
Some will surely say that such things should not be part of the rules, and that's a great mistake. If you want a game in which it's fun to choose a sub-optimal strategy in combat because of some "personality traits" or "character's driven goals", you need a way to make it count.