I take it you play the Sentinel or Gunslinger in that setup? It's always easier looking on the bright side and having faith in Bioware if your class is extremely strong. And what you said there is just PvE, there's DPS classes hurting immensly in PvP as well - in some cases because of sub par burst, wonky usage or crappy survivability. And in PvP you will need to get the best class setup you can, if you're serious and want to try and get as far up as you can.
Class balance is not good, and they need to address it in 2.4.
I'm the tank in that group, and my tank is a shadow. Don't talk to me about broken classes. Believe me, I know. :-)
I tank on a shadow post-2.0. I healed on my commando even pre-2.0. I rolled a Combat Sentinel before they were FOTM and Ataru was seen even less than Shi-cho. I brought a Lightning Sorc into progression raids pre-2.0, and I very nearly main-swapped to the most energy constrained, razer-edge DPS spec in the game because I thought it was fun. It's not as if I don't know what it means to have a class that is very difficult to play viably. Things are so
much better than they used to be in terms of relative class balance. And that's speaking as someone who mains the most broken Advanced Class in the game.
I do 100% agree that PvP DPS isn't as well balanced as PvE. I would be willing to take almost any class and spec to almost any encounter in the PvE endgame, but I just can't say the same thing about rated warzones. Unfortunately, there is a purely mathematical argument to be made that this realm will never
be balanced due to the number of specs in play, so I don't hold out much hope here.
Taunts and off heals provide marginal utility in very specific settings. In most cases, a taunt will get you flattened and an offheal will kill your resources(unless lightning sorc) and be worse than bringing a good healer anyway.
My experience contradicts yours. At a minimum, an off-healer brings a battle rez. We almost never have our healers rez, since if someone died, it usually means the healing was tight enough that they don't have the GCD to spare. As to the off-taunt, it really depends on what is going on. It's one of those things that you never want to use, but which brings nearly invaluable benefits when things have gone haywire (e.g. tank temporarily down in 3rd phase of the Dread Guard; off-taunt takes the Leech).
They're good in PvP, sure, but in most pve encounters, bloodthirst and ballistic shield provide more utility in an ops group.
I love ballistic shield, which is part of the reason why I like having a gunslinger. You rarely need two of them in a row though. Bloodthirst is great, but believe it or not, its value is actually substantially lower (by a factor of 10!) than a simple armor debuff. And overall, why settle for just one or the other? I like to balance the utility of my raid group to the maximal extent possible.