2360: Battle for Cydonia (the better, imo) I didn't care for it. But Heavy Mach 2 was a big hit but alot of grinding. Both are top down viewing but check them out. They are not bad.
I really enjoyed Giant Fighting Robots. It takes a bit to get used to, but it's a pretty good simulation-style mech game. MetalWars is fun too, it's a bit more of a generic dual-stick shooter, but you can build your own mech choosing from leg pieces, torso pieces, and arms, kinda like a scaled down Armored Core.