Greeting, Enigma, Landslide, Gates, Whirlwind, Maelstrom, Cry, Chilling are all good for mostly melee combat in one way or another.

Forsaken, Fortress, Place, and a couple others if you're worried about magical/mental type damage.

I mean really there's a lot of good legacies for giant warrior. I can think of a few that I would steer clear of - STSF obviously, as well as anything that relies on dodginess.