Great idea for the mod, i always wanted something like this. They can work as an endgame crisis or a mid level threat.
Regarding the design of the ships, i have some fixed thoughts. The ships that resemble bugs but that are not actual bugs look great. But the ship that look exactly like bugs break immersion for me.
Like i can imagine a hive making bug like ships floating space arround but like bugs actually being the size of ship and looking like beetle doesn't fit.