I completely agree with you. I'm a lvl 50 Merc, and I do love the class. When it comes to PvP you do get people who just spam TM like there is no tomorrow, but those are the kids that rely too heavily on the 1.5 sec dmg in big numbers. I am by no means geared perfectly or amazingly for PvP so my TM does on avg about 2k dmg or a little more each hit. But it's the bonus for unload and railshot that make TM so necessary. Pop 3 to 4 TM on a target, lower their armor, then unload with 25% more dmg, and railshot with their weak armor. You will see a massive dip in their health almost instantly. We just happen to look very grandiose when we do it, so like you said, it get's noticed a lot more.
Spamming TM doesn't denote lack of skill either, it shows someone who understands the concept of a very good strat. Not a perfect strat, but every class has that 3 or 4 move strat to enter a battle with. After that, it's just hack and slash until cooldown is done, or just blow em up with a heat seeker missle if your a Merc (which by the way is also very noticeable when used on the battlefield).