I'm just going throw this out here, I have no idea if it's possible, but I want to make sure it's noted: I want to be able to attach devices and vehicles to another vehicle such that they:
1. Stay still (ie, are actually attached, like the warthog to the Pelican in campaign) and
2. Can still be utilized.
Basically, something along the lines of how Halo 2 does a number of things.

Again, absolutely no idea of how feasible this is, but if it can be done, it will save me a significant amount of work (and allow me to equip my ship with extra turrets)