I like trying to go with an Astromech other than R2-D2. He's taken too often. I will say that he's excellent on an ARC-170 due to all the green, though. You could also probably go with R5-D8 and start to remove all the hull damage on the ARC-170. It does have a lot of hull.
It will also be good with Extra Munitions, as well. I always think of it as a torpedo boat.
Vectored Thrusters will see a lot of play in HotAC.