Hmmmm, I have those same concerns, but I think with some of the changes in 3.0 and A LOT of creativity they'll have a much better chance. For instance to keep melee off there's disengage+ Frost traps and also deterrence which will give pretty much 5 seconds of invincibility.

What mostly draws me to this is the fact that it hasn't really been done before, it's a challenge, a huge challenge and I like that a lot.
The other thing is thinking of 5 huge red pets reeking havoc. At this point it's all just theorycrafting, but since I really have nothing to go off I have to start somewhere.

I also think that BM will be a much more solid choice of spec, even though Survival is more OP, both could work though. Lock and Load will definitely be a part of any spec, I don't think anything can survive 12-15 arcane shots.