In my experience as a Cloaker most people do not have Darklight and hardly anyone has Audio Amp. On several occasions I have snuck into Base CCs and hacked them right in front of several enemies and even somtimes I escaped. Darklight is only difficult when used my MAXs guarding CCs but that is where Boomers come in.
As far as 2 pistol slots goes, its just not gonna happen. I think we all know its not going to happen at least in the near future because Infiltrators are already ausome assassins. You just have to become a master of the inventory switch. Hardcore infiltrators are usually: Adv Hack, Adv Medic, Combat Engy + vehicle and perhaps a MAX suit. In a loadout that utilizes all your abilities you have to switch up to 4 objects out of your inventory. Even with 2 pistol slots you would still be switching 3 objects. As far as the REK specifically goes, mastering infiltration under fire while getting the hack for your team and not fumbling your REK is what skill is all about. It is kinda annoying at times but it gives another way for really skilled infil/hackers a way to shine.
Finally I wanted to address the "cloakers are not team players" idea. Cloakers just do not do what other squad members do. Sometimes they follow behind for the hack, but many times they are working the edges of battle to find that AMS or doing sabotage. These are all invaluable and support the Squad in an indirect way. Also Cloakers are the best at battle rez since they can go unoticed
