I think SWAT class needs to be modified so it becomes more appealing, but not like this. Combat shotgun is the only exclusive advantage the attacking team has, while protectors have sawn-offs, deagles and M4s. They shouldn't be given more good weapons.
I have the feeling that you're suggesting this because you are spending these days as a cop fighting a bunch of well-known terrorists that are constantly doing combat shotgun drive by, huh? And you want a class similar to theirs so you can have your fair war.