Are you suggesting to dip BFS into the atmosphere to do inclination changes? That is how I read your post.
I think X-37b might be able to do those kind of inclination changes, too. BFS should be able to do a similar thing. I have no idea why the USAF wants the x37b for, but ITS should be able to do the same job. Except not very stealthy (if that's what they're looking for).Anyway, yeah, it should open the trade space a little further. Large amounts of on-board propellant AND the ability to generate significant lift.
Why bother with a new vehicle when you can use a BFS with few modifications? Heck, with cleverness you can use a stock spaceship with custom equipment in the unpressurized section. There's a huge door there already.
You will need some sort of horribly complicated (and automated) conveyor racking inside the ITS to transfer satellites around so they can be bunged out of the door. A door note, that's not intended to be used in space (AFAICT). If you are fitting 240 satellites, the internal storage system is going to be a nightmare within the constraints of the ITS.
If SpaceX is doing the whole thing (production and launch), they would probably skip insurance.