Playing Heroes

I've recently discovered that my PS3, despite not running PS2 software, does run PS1 software and so I've been replaying FF7 and Chrono Trigger. This has driven home something about RPGs that I've missed. I've missed playing heroes. I've missed running games for heroes, for people who are inclined to do the right thing. I understand that there's plenty of self-interest in the world, but I kind of want to run a game where I don't have to appeal to that to motivate characters to do right by people.
There's plenty of space for the self-serving, but it seems that every game I run seems to be for characters who are hard bitten and in it for themselves. I want a game where the characters have the occasional moral pang or instinct to do the right thing. I think the next game I'm gonna run I'm gonna specify heroes.

EDIT: I want to clarify. This is about tabletop, not LARP. LARPs thrive on self-interest, die without it. What I want is to run a tabletop game where I'm not herding people constantly towards plot. I feel like Roy in the second arc of Order of the Stick, trying to get people motivated by lying about treasure and random giants.