One sweet feature that other software has for DSLRs is a ‘lens focus’ option using Nikon/Canon SDK. You can use the motor in the camera body to manually focus using controls on screen. I can do this with qDSLRDashboard and I know other astro programs can do this as well (at least for Canon).
It would make me more willing to drag a laptop (and SGP) into the wilderness if I could have this feature. I’m sure other DSLR users would like it too as it would let you compete (implement features they don’t have when it comes to NIkons!) with the ‘other guys’.
Another option, since this is specific to DSLR users, would be to make it a module and we could pay a little extra for it.