I'm guessing this problem is and will be short lived. If you consider the POV of the devs, they know that tanks are very often bottlenecks in dungeons and raids. As well as coordination and group/class/spec balance. What they did was make the first Tier of raids forgiving on all fronts so we can get our foot in the door and absorb the guild fluctuation that occurs in any new game. This is the exact same scenario that happened in Rift. Hammerknell came out and the story changed dramatically (for the better). I expect the same with tor.
I'd suggest holding tight...don't let the tanks in your guild get bored or drift away, trust me you'll need them very shortly.
I'd assume (and hope) that the next tier of raids will require off tanking, greater coordination, greater dps and competent healing. Much like you want.
Like your toons the raids will progress.