Op my guess is you have not been pvping for very long, or you are new to mmos. Thy can not limit classes without DRASTICALLY increasing the wait times for wzs. Point two pvp is not pve. This means you can not line up your ducks in a row and count on victory. Nor can you calculate whos going to win or whose going to loose until the end of the match. This is pvp. This is also why many people complain about pvp more then pve, because people expect to go straight up the middle, and kill everyone on the other side. Instead what happens is the other players from the other team and up wiping the noob off the face of the planet.
As for smash give me a break. Ive pvped enough on my commando to tell you that smash is the least of my worries in the level 50 bracket. Now running into a stealth operative or powertech with fire, that is at the top of my mind to avoid. Oh and mercs too. Those rockets still hit like a tone of bricks. Ironic everyone used merc rockets as a reason to nerf grav round. Now that grav round has been nerfed the imps have free reign with rockets lol.
As for the first part, I'll agree. The second.. well I don't know what to say. Are you saying smash is fine, but you have to worry about your mirror class? You realize tracer missile was nerfed along with grav round? I'm not sure if this is a joke. I'll give you that a good concealment operative or powertech will wreck you as a gunnery commando, but then nearly any class will 1v1, especially if they have a pillar to LOS and use their interrupts correctly.