All the destroids are fine
For wasps and stingers the veritechs will be large, but i think with some posing to have them in crouched positions and such you could easily get away with them being 20 tonners (plus scale is all over the place in BT). Supers and Armors will likely be on the large side but again, i think some creativity will allow them to be used. Marauders will be very large, but i am going to look into chopping them down a bit and seeing if i can get them to work. But all in all, for $5 each at retail, some good cheap mecha forsure!