I loved Red Dead! It's been a hell of a long time since I played it though. I tend to get bored with games very quickly but that's the only one I ever got even close to fully completing.
I lost interest though after trying to transfer my save games from the old white 360 to the slim black one. Something went wrong and they became corrupted and I was too disheartened to go back! I've moved onto the Xbox One since as well.
Atm it's the new Assassin's Creed I'm most into, and Titanfall is the only shooter it looks like I'll stick with long-term, can't stand either COD or Battlefield. In fact, throw in FIFA 14 and those are the only 3 games I've got for the One right now!
On the graphics difference between the One and the PS4, currently the PS4 is capable of outputting a HD 1080p resolution, and the One only a 720p HD resolution. However, the One's hardware is capable of outputting 1080p. The developers of games just need to figure out how to do it through the Xbox's new memory management system, which was built from scratch specifically for the One, and no-one knows how to get the best out of yet.