Role playing is confined by the boundaries of the situation the character you play finds him/herself in. The freedom to go off on a alternate universe tear likened to good Kirk, bad Kirk does not a good role playing game make. It's a nice feature, but that's it.
For example in FF12, your main character is a young street urchin who lost his parents to plague, his brother to high court conspiracy, and has been watching everyone he knows get crushed under the boot of a conquering kingdom. Before he even has much time to parse his situation, and what to do about it, he is swept up in the resistance spearheaded by the queen, who is claimed to be dead, a loyal knight of the queen who was branded a traitor, and a cast of 3rd parties like the Sky Pirate Balthier and the playboy bunny with a head on her shoulders, Fran (I love these 2, they make the story charming).
By probability, peer pressure, motivations, and conditioning, most of his choices are already set in stone. Getting there is the only thing left to choice. To have the freedom to go against, character, story, and what that character really would do in that situation makes for a horribly bad playing of the role, not good.
To me what makes a good RPG are... Is the story good and does it make me believe? Is it fun? Do I find myself liking the cast? Is there enough depth to keep me interested? Will I want to play it again? Will it surprise me with added value and unforseen replay?
There are also other factors that are more personal like preference for turn based. Larger than life bosses that are different and complex. Puzzles hidden in a secret, wrapped in an enigma is a plus. Fanbase level quests like figuring out how to get the best weapons, hidden things that usually no single player will discover on his own is something I like too.
For me, min maxing is required. I find it funny all the people who whine about min maxing, and 9 times out of 10, they min/max the hell out of the characters they play. So many times this has occured, is so funny to see. I don't say anything, just chuckle to myself.
PS3 resurgance by GOW3 - Check! Mass Effect for PS3 - Check! Diablo 3 for consoles? I say "For sure"!