I'm always surprised about all this complaining. Every class has a counter one. Sentinels/Marauders and Gunslingers/Snipers deal the most damage because their class is meant to do that. I think people need to learn how to roll play. If one chooses to be a tank they can't pretend to deal much damage but they will have high resistance and CC. In the Knight/Warrior class Focus/Rage spec case it's a matter of choice, once again. We get the super Smash and basically that's it! It's not that Force Scream or Crush deal tons of damage. And as far as melee classes go, realistically speaking, two lightsabers up the *** would hurt a lot don't you think? Ranged classes have their advantages too, just learn how to use them. What do you want? An Assassin in tank mode with heavy armor and self-heals?! No, forget it. There is no FOTM class, it's just the person behind the screen that makes a difference. If I know my class I know what is best for it. I would never use my Operative in a group fight because I would be useless. Instead I take down single targets because that's what the class is for. I presume too many players want their class to be omnipotent in every aspect. In MMOs it doesn't work that way, deal with it.
I love my Marauder but if I'm stunned and don't have my DCD up I'll die pretty fast, but that's how it's supposed to be, as with every other class, each one has it's defects. If I find an Assassin I use Ravage and use other abilities that are not Force related, simple as that. All I can say is that the Juggernaut suffers more on this aspect because it has less overall melee damage, but when I had a Juggernaut I would always beat a Sorcerer hands down instead.
I could go on for a while but you've got the point.