Nais..
My druid team is parked at ~25 (i'm not even sure O.o)

I've mixed my main account druid for a shammy for brd spawns and it seemed to work out great.
Maybe even better then 5 shammies once WotLK talents start counting.
To bad the shammies always find new stuff to grind and they like to stick together.

The only thing which I think is going to be troublesome is handling the shapeshifting if you start going tank-healer-3oomkin.
I for one would love to macro the possiblity to swap the healer and the tank in mid combat might the healer go oom.
But hey, no trouble, no satisfaction once it works

Good luck and keep us posted