Huh.. like minds. I have the same issue myself, though my approach on the desk last night was to remove all the sgements above and below the BCannon mounting. It keeps some bulk but loses over 15mm of height.
I feel most opponents would get upset having a smaller target represent a much larger cousin.
Carving up the column is best of both worlds. Reduce height but keeping overall bulk.
I'm also in the camp of keeping the gear aboard like a mule. And agree, a nice house rule would be within 3" ammo support.
EDIT: I do like the smaller BCannon drones though!