Love this game, though I'm not far into the story because most of my time has been spent dicking around and letting my friends play with cheats on instead of doing missions. The game is really glitchy though, some are funny but sometimes its just annoying.
I agree with donut about weapon selector, i guess its something you have to work at so you can switch really fast. In my opinion the game should pause for a second while you choose, like I've seen in a few other games (though obviously not in multiplayer).
Having cars and possibly planes would be cool, possibly added in through DLC (though i haven't beaten it yet so if there could be for all I know.) I really hope this comes out for PC though and modding is possible. I'd love to see someone put some GTA4 content in there (they both use the RAGE engine). Can you imagine how much fun it would be to ride dirtbikes on that terrain while shooting in dead eye? Though I am talking completely out of my ass right now, one can only hope.
E: 2000th post woohoo....err yeah.