I have a very hard time not going Breton. They're a jack of all trades and their magic resist is hard not to pick.
It also doesn't hurt that a lot of the other racials are pretty useless and most of the rest are easily replaceable. Kajit claw damage is a notable exception for unarmed playthroughs (though that also is pretty niche), and there's just... something about playing a Nord in Skyrim.