Don't the rules say that anyone with a comlink can control one drone? Maybe the answer is a good comlink + microdrone and let the drone's pilot program do the shooting?
1) There's a difference between being a Rigger, and being a drone owner. Anyone can go downtown and buy a drone, and order it to shoot stuff. You don't even need a Commlink at all, except they're the cheapest way to get a high rated Firewall.
2) Any device can protect (Device Rating x 3) other devices. So even a Rating 1 Commlink could be Master to 3 different Slaved devices, such as drones. Not that it would be worth the effort, since drones would have a better Firewall than a Rating 1 Commlink could provide.
3) Back to the "not needing a Commlink" aspect, if you're relying on the Pilot program and the Autosofts to do the work for you, then all you need is to tell the drone what to do. "Shoot those guys over there" and off it goes rolling its own dice.
But yes... as often as you may see a teammate carrying a machine pistol or SMG just so they can lay down covering fire, you'll see some teams that go get a cheap Roto-drone with a mounted machine gun, for the exact same reason. The basic Pilot program, with a cheap Autosoft, is more than enough dice to make it worthwhile.