In XCom:EU, Floaters always struck me as a slow race. Their floating apparatus seems like they are just floating along. Can't run with no legs and it doesn't give much of an impression of flight. In the remake that's entirely different though. The Striders could well be faster, but maybe have less stamina since it's more exausting to run around than to float.
I'm thinking Floaters overseers with rifles/sniper rifles + Striders grunts with Alloy Sword and pistol/plasma caster/grenades would make an interesting if nasty combo.
Spawn the floaters outside where the long range high accuracy weapon works well, spawn the striders inside where the melee in tight quarters will be nasty. Hum..