Tuned Actuation is still probably the best choice, a great general buff that really increases mobility.
Ground Zeroed is the most interesting. You can stun people for 2 sec if they fly towards terrain after hitting them with your ult – it’s pretty awesome but more situational than TA.
But then there’s… ugh… Aerial Barrage. I myself am not sure entirely how this works, but… ew. 113 damage? Even if it’s 113 per grenade, that’s still bad. And it drops it on takeoff. Why? Caldy uses his ultimate when he needs to chase people, so if he launches from far away, it’s pointless. Even if he launches a foot away from his target, unless they’re standing still for two seconds, it’s still relatively pointless. You’ll miss them. And if they ARE standing still, you’ll tickle them.
Now I’d like to know more about this thing. How big is the splosion radius? Is it 113 per nade or total? Is it boosted by skill damage?
EDIT: Eeeeeeeeeeeeeeeeeewwwwwwwwwwwwwww. I just realized that it doesn’t drop two grenades, it drops one. Ew. Nasty. Really nasty. If it was two it’d be so much better. Not good, but better.