I've got a couple hours in now and the learning curve is about what I expected, but I'm enjoying myself just getting used to everything. I've rebuilt my AC 3 times already, and I think I finally have it how I want it (for now anyway). My weapon setup is:
Left hand: Pulse machine gun
Right hand: Battle rifle
Shoulders: Missiles
Right shoulder: Gattling gun
Left shoulder: Beam sword
When I'm around large groups of enemies the gattling gun just tears them up.
As far as controls andw the like, I'm still really clunky with my movement. It's going to take me a while to get used to how these AC's move.
Graphics and the like are OK. Nothing to write home about, but they do the job. The FPS is fine, and I haven't noticed anything distracting yet which is a good sign.
The only issues I really have with the game so far is that you spend so much time loading all the time. Go to a screen and load. Go to the next screen and load. Once you get in the game, you're good, but navigating the menus is a bit of a pain.
Also, the online is a bit wonky right now. Some random disconnections from their servers, and the like. Hopefully they get that taken care of soon.