The over the top flips being standard feels a bit weird (although I do like the one where you summon a bunch of bullets) but overall I like the 'gunner that deploys robots and gadgets' theme.
I don't particularly like giant multi-tool though, I'd rather have the robot turret back.
Have it transform/deploy various things i.e. pops out a flamethrower and starts spinning round throwing fire everywhere for AoE, flips out a minigun and goes to town for ST, deploys an electrical field on the ground for a DoT effect, transforms into the automaton queen and rushes-in for the big melee mode attacks. & so on.
MCH doesn't really have a lot of skills, I feel there is plenty of room to add enough that both "gunners" and "engineers" can be happy.