Every new guy i see now, plays assault for one battle, then starts a new character as a heavy, because they get vaporize by them almost instantly. ( True Story )

You are an assault, the easiest class to play, with an assault rifle, the easiest weapon to use.
At low skill levels you are barely vulnerable, at high skill levels you are nearly unbeatable.
Yes, the easiest class to play, when skilled up, is also the most powerful class to play.

You have speed comparable to a scout. You have shields and armor HP totals, that when leveled up, is on par with even mid-level heavies.
Your assault rifle has next-to-nonexistent sway and kick.
You have an instantaneously stone-statue-still ADS.
Your assault rifle has dps so high that it doesn't matter if you're shooting a target that's beyond your already laughably far optimal range; if the bullets can touch that person, that person is dead.
Your gun fires 2-3 bullets for the price of one, so it's actually a mini burst rifle automatically. (Go ahead and tap your trigger and see.)
You can fire your gun indiscriminately without penalty. Your weapon does not overheat, you have no chance of accidentally blowing yourself up, and your clip is almost as long as an SMGs.

Quite honestly, with all that going for you... you have no business complaining about heavies dominating CQC, and snipers dominating LRC, because everything in-between belongs to you.
You get pissed at a sniper, you run to his perch with a LAV or some other vehicle and kill him.
You get pissed at a heavy, you shoot him across a field or at a distance down a corridor, and some of your kind can even beat heavies in CQC.

And the ONLY thing that seems to slow you guys down when you're travelling in packs, is a barrage of flux grenades.
You have nothing to complain about, except the unreasonable nerf to the Breach and Tactical ARs.

So just bite the bullet, squad up with some of the more skilled assault players, and learn from them how to play your class; because honestly any kind of complaints coming from your kind, imho, is whining and tantamount to trolling.