Tactical Assault Rifle should recieve:

Minor Damage nerf 5-10hp

Minor Range nerf 10-15m

Rate of Fire Nerf in the form of not firing faster than the animation

Minor Hip spread increase.

I would not say the Tac needs a dmg nerf, I'd rather go with a clip size nerf.
Cut that klip to 10 or 12 rounds. It's a tactical gun, why does it have a clip like an automatic gun?
Just look at this: base dmg is 78. A Proto suit has around 600 HP, equals 8 shots to kill those poeple, we are still talking about Proto! 8 shots and we don't count headshots in, so you just have to hit with every 3rd shot from your magazine to kills someone. Well this is not tactical at all.

You want a tactical gun? than you should be forced to use it tactical, and not as a bullet spamming close range sniper rifle.

And yeah I used the Tac and I can say:

Inside a building. ->pwns

Hilly terrain. ->pwns

Inside a complex area on the road or similar. ->pwns

In area's with lots of cover in the form of installations, walls, fences, etc. -pwns

Any other areas I haven't mentioned. -pwns

This weapons is a killer in every aspect of the game. The laser in chromosome was by FAR(!) not so OP as the Tac is in uprising, but you simply don't see so many nerf threads because all the AR guys don'T wan't to accept that they hold the most OP weapon in Dust in their hands, right now.