All of those seem pretty cool. The pen gun's cost and damage are between the stetchkin and revolver's (stetchkin = 20 brute, revolver = 60 brute), but unless the gun is silenced and shows no attack messages or projectiles, it'd be fairly obvious who the shooter is and you'd be exposed right off the bat.
Mind Hack dart seems pretty expensive, as if you control someone and make them do something illegal, if they are searched and nothing is found on them, they obviously wont be charged with EoC as they'd probably be believed when saying they were forcefully controlled, you'd need to slip some traitor gear onto them too, or not much will happen, and with only 4 TC left should you buy it, there isnt many options. For a one-use, third-of-a-minute controller, I'd say drop the price a bit.