What I want in a roleplaying game.

This is not about anyone, honestly. It's just what I want.

I want to be a player in a roleplaying game; preferably D&D, so I'll use that as my touchstone, but honestly any game that had the important bits would be nice.

I want a game where the PCs are all comrades. Not necessarily friends, but comrades who don't waste time with petty bullshit. As illustration: one of my favorite games was one in which my character and another didn't much like each other, for both good and bad reasons, but we worked together nearly flawlessly, because "we" both knew that, at the end of the day, we were on the same side.

I want a game full of discovery, of adventure, and quests that matter, even if only to the characters. Plots that are more than "X hired you to do Y." I want to save the world. I want to delve into ancient ruins and find artifacts and long-forgotten spells that aid my character in his quest--or at least make it more of an adventure. I want long (objective, not subjective) treks across nations on horseback or on foot (or, dependent on genre, frequent treks across the galaxy). I want my character to have a destiny.

I want my Fantasy game to feel like it was shot in New Zealand by Peter fracking Jackson.
I want my Sci-Fi games to feel like George Lucas made it but Joss Whedon or JMS wrote it.

I want to play in an epic.