Once your toons are more geared, you'll always have the option of finding yourself a dedicated healer friend, to even things up in that regard.

It is an interesting composition for arena.
It is good to see people thinking outside of the box, so to speak.
Mages + Priest; Rets + DK; Locks + Heal; Rogues + Heal...... etc... more options then 4x Shm.