I love how the Rainmakers look so, for lack of a better term, grunt-like. They look like soldiers, not characters. It actually makes them more interesting because you don't know what they're thinking. Whereas with Starscream you always know what he's thinking, "How can I try overthrow Megatron today?". The Rainmakers could be thinking, "Ugh, that energon burrito isn't sitting right. Oh no! Where's the Lil' Tetra Jets' Room?!" or "If I transfer my credits to a long term mutual fund, I could save 18% in taxes" or "Only 2 days till retirement! Oh wait, what's that? Autobots incoming! Ahhh! Ouch! Blarg! Dead."
Or maybe that's just me reading way too much into things again.