[Wrana]

I'd say that the "bad Bandars" idea was buried some time ago. They DO have a disadvantage in siege due to "animal" tag, however. Still, they work good enough - and they often have Elephantes with them.
Super-high research cost will probably help Bogarus somewhat - and they have mages to research faster than opponents. Still, this will postpone the time when their powerful summons will appear...
Actually, I think that extra-slow research will change the normally perceived balance in many cases - including making some low-research spells/summons viable. Maybe it would be interesting to test it...