I've definitely toyed with this idea. Gun emplacements generally would add a lot of gameplay potential.
Imagine: if you could carry a gun emplacement in your cargo bay, land at it, set it to attack whatever (for instance, friendly targets, or even just monsters). Of course then cities could have their own gun emplacements programmed to target monsters that fly nearby. It's sort of funny when higher level monsters destroy cities. Hehehe =)
So I will add it to my list! No promises, it's sort of along list, but I'm finding I still enjoy adding stuff to VtV and I think it's a great idea generally.
PS Thanks for purchasing!