I think the aliens look like "tech-organic". Just watch the final part, with the alien "ship"? rising out of the debris. It looks like it absorbed part of those debris...
Anyway...looking at my miniatures, I'll use both Therians from AT-43

and Marro from Heroscape:

Maybe they'll be 2 races...or unarmored and armored elements of the same species. What do you guys think?