I have a suggestion. If a support perk is the way we are choosing to go. I think there should be the DT perk Jovanka is talking about, but how about this:
Shotgun Surgeon
Requirements: Small Guns 150, Doctor 100
Bonus: Aimed shots with a shotgun are significantly more likely to cripple limbs.
This gives the shotgun a different role than an smg, which is what I feel we are trying to do here. Now instead of being just another high damage mid range weapon, the shotgun becomes a counter to big guns and snipers.
I could see myself creating a 2 aimed shot shotgun build, (with jet or 2 action boys obviously) for the sole purpose of countering BGs and Snipers in PvP.
Imagine it, people are fighting in town for TC or whatever, they turn a corner or enter a building and BOOM you cripple their right arm. Guess whose not using their weapon any more? With two aimed shots you can double tap, BOOM BOOM, eye damage and crippled right arm. Did you kill the player with those aimed shots? Probably not, but you have rendered them useless. Making the shotgun a type of utility weapon for crowd control.
I know what you may be thinking, "well this just sounds like a mid range sniper." So make it so that the perk doesn't rely on crits. This way it doesn't have to be another 10 luck, more critical, even more critical build. Giving the player much more versatility in what perks they want.
*edit in name and reqs.