Please take this with a grain of salt, since I'm still a student, but I really can't help saying a few things about the design, especially since it looks like you put a LOT of work into it and are planning to put a ton more in the future.
OK, so this is really amazing and I like the design direction, but there are several problems with it so far (in my opinion, I guess). First, it looks too similar to the reaper. I mean, yes, it has a different chassis, but the immediate read of the mech says reaper and what's causing it are mainly the legs: the structure is too similar (also, their design is too blocky while your body only consists of organic forms). Try experimenting with how you imagined the silhouette (like, the infiltrator kind of looks like a monkey when jumping). Second, I think your secondary details are too prominent. If you look at the infiltrator (again) for example, you can easily read the main forms and the secondary details are there just to compliment them (tertiary details are hardly noticeable unless you're admiring it). And following that, your secondary details fight your main forms too much. As I stated before, they should be used to emphasize the main forms--they aren't their own thing, that's what your main forms are. And lastly, the proportion of the legs should get smaller as it moves down. Thighs are largest, shins are second, feet are smallest, etc. Look at the infiltrator's legs again after removing the boot (the flat part), they follow this pattern. Look to real animals for reference on unique ways to accomplish interesting leg designs.
Also, I hate to say it, but your new coil rifle is a little too compact for Hawken's weapon designs. Your old design actually suited better (you just have to break it up into small, medium, and large shapes instead of stacking it like bricks). Maybe look at other weapon designs for inspiration on how a railgun-esgue weapon could animate, always thought the grenade launcher looked kind of like a lightning cannon, personally.
Hope you can take something from this.