Game was fun enough to keep me entertained long enough to beat it. As someone said before, the wall crawl legs make the game much easier than intended I believe. The only level I didn't just walk to the end and crawl up the building using the speed boost was the last level, only because I needed the shield to get past the final enemy. I actually really enjoyed the fact I had to switch gear at the end and think about how to get past the mech they send out.
If you make a second game, I would love to see more of that. I never took off the cooling armor, but maybe force me to switch because colder planets can freeze the bot and you want insulation armor? I always used the cannon, maybe on high-grav levels make the cannon near useless because of weight? Same thing with the add on mech teammates, give me more of a reason to switch. I thought I would need to on the scorpion level, but I could speed walk through to the final wall like all the other levels. Maybe dont allow me to walk through the smaller mechs?
Overall, fun game, would play a second release. I don't think there is much replay value, maybe add an infinite round? Or a role reverse where you defend a tower? By the end of the game I had unlocked everything (except the secret special which I saw no clue as to how to get it) maybe have a high price super cannon that just destroys stuff that you need to beat the game to purchase?