I like that Hawke actually talked and wasn't a silent protagonist. And I always chose the sarcastic option so he was really funny.
It was also cool to see a game where time passes and you get to see how events play out.
Aveline was my favorite companion. We were BFFs.
I was a dual dagger rogue and nothing could hit me. Most of the time I didn't even need a party to kill everything, but having them around sped things up. I usually brought Aveline, Fenris, and Merrill. You don't need a healer in this game except for that one dragon fight maybe.