I really don't know if I can really boil down my favorite things because there are SO MANY things.
I'll say this. I think this is easily my GOTY now. I played on PS3 and the biggest letdown is the constant freezes I've endured. Besides that I've literally enjoyed every single moment. Also consider I'm at like 90% with the entire game. I've got like 15 challenges or so left. Everything is so fun even the mundane collecting shit part is infinitely more fun when your listening to Riff Raff.
"If I just blow up another statue Codeine Olajuwon will acknowledge me"
I love this game. I even don't get too burned out on the side-quests. Mostly because you can 'super-power' your way out most of them: Telekinesis mayhem? Take the ball and super sprint through the city. Senseless destruction never gets boring!
Yup love that one
Like really the only side quest I don't like is the one where you need to TK throw things into the targets