How about ruling that having the Deathroller counts as having hired two big guys for your team? That way, if you buy a Deathroller you can't get an extra Ogre, Yhetee or Treeman for your Bright or Light team. Of course, the DR would still remain problematic, but at least there would be some kind of *trade-off* involved in buying the blasted thing, some kind of disadvantage associated with it, which is certainly not the case right now.
It should also be made more expensive.
EDIT: Let me restate that, in and on itself, the two big-guy limit is a step in the right direction, although it is actually counterproductive if the DR remains unchanged. Concerning the Jade Roster, you should not consider the fanatic as a big guy (thus allowing him to be fielded with two "regular" big guys like Trolls), and you should probably change the third "race" into Ogres.
EDIT #2: And did I ever mention that better maps are essential? Once or twice, I think
