Really like how the game is shaping up. I wasn't sure where you would take the game next since all the obvious areas are finished but I sure wasn't expecting aliens.
Honestly, I'm fine with futa content but only really like it if the futa is the dominant one. For that reason I'd prefer the enemies to be the only futas and not the trio. Hopefully that's where you're taking this idea.
Still, if the doubling of atwork gets to be too much for you by all means either scrap the idea or add it in later on so you don't get burned out.
Since Selina seems to be the only one with actual freedom will she be the protagonist for this section?