Commando wasn't "overpowered". People just hate dying, so they'll exaggerate how effective something is, if they don't die the way they feel they should have.
With that being said, I used Ninja Pro. I felt it was much more beneficial, I didn't need to bring a knife to a gun fight anyway. I liked not having to worry about HB Sensors getting me and I loved not hearing my footsteps.
However Hacker is in no way OVERPOWERED because that word to me is used by crybabies. However Hacker Pro seems to be a Noob perk because as the OP said. A guy who is terrible and can't get his own killstreaks will just hack yours. Similar to those guys who'd be 3-18 but always shoot down your UAV or KS