Finally got around to trying this and liked it a lot! The aesthetic was pretty spot-on and the combat felt responsive.
Regarding the right-click aim thing: I actually liked it, but I think for it to really click I would make the mech take longer to turn/aim, so that you can look around with quick glances normally but that right-clicking is taking the decision to re-orientate the mech.
The only other thing I would say, is I wasn't sure when I was being attacked. I think the feedback for damage / enemy firing could be beefier.
Overall, great job!