I suggest:
#1 like regular patrolling vertibirds, upon landing, this vertibird drops a small squad of BoS allies. This way (if you use the vertibird like I do), you can call down a vertibird before you enter into a place, and you can have a small, temporary squad of BoS soldiers help you out.
The Minutemen artillery could really use a bit of love
I suggest:
#1 If I made the heavy investment of 5 settlers on 5 pieces in a settlement, the delay between the calldown and the barrage should be no more than 5 seconds.
#2 Like the flare, there should be a launcher for the artillery smoke grenade so that you can call down barrages from a better distance.
With these in mind, I wouldn't mind measures being taken to reduce the availability of the a munitions. For example, you could slow down the regen rate at sanctuary for the artillery grenades, and you can quadruple the price of vertibird grenades at Teagan's shop