Well, I've only done one run so far but my squad never had this problem. 1 cleric, 1 veno, 1 sin and my barb (aps) first of all, we didnt even die much. And second, it really isnt that tough to hold the fort after the tank dies. If barb and cleric dies, well, then you're fcked. There is a teleporter to the last room, would be nice if there was one for every room but I don't really feel the need.