Machine Guns with Close -2: I was thinking the same. The mitigating factor for me was one of balance. You can fire an AR with Firearms which gets you Pistols, SMGs, Sniper Rifles, and Shotguns. To use a Machine Gun you have to spend a whole skill slot and spend separate skill points. I didn't want the Heavy Weapons specialist to have to choose between blowing himself up (Launchers) or getting the -2.
I still might though...
On the other hand, I was thinking for both Launchers and MGs as Close: No.
I put ARs on my drones in Anarchy Threats (medium drones)