So far my favorite thing has been ganking the lookout on the raider cave I had to clear out. When I approached him he had the same dialogue options as everyone else, and he didn't attack me on sight, so I figured he was a "good guy." Then I checked my journal, realized he was one of the raiders, and circled back to try and sneak attack him.
RAIDER: Boy, what a pleasant young orc w/skull helm! Maybe I was wrong about--OH LORD THE PAIN!!!
He kept trying to run away to shoot arrows, but I kept bearing down on him, and I trapped him in a furrow in the cliff and just wailed on him with my axe. When he fell I looted some chainmail and a longbow and left the clothes and the body until I had gone in and killed his friends.
One thing I don't like is having to switch to magic to go Berserk as an orc. It's their racial ability to go berserk, and I think that having to cast it as a spell is silly.
Oh, my second favorite thing is when I bought my troll skull helm from the armorer in Balmora and I traded him my nordic plate helm (it looks like an iron helm with ram horns), once I closed the transaction, the merchant immediately put on the ram-horn hat. I don't know why, but I thought it was supremely funny, and every time I go back there, he's wearing that hat.