It looks impressive, but often morale hinders them if the heroes are from different factions.

Well, I don't know, I always try to choose a more diverse team... if the heroes are already well-leveled, then morale doesn't bother them... there are useful artifacts, and everyone can be equipped in the forge... I usually take 2 Chaos Mages and 1-2 Chaos Warriors + a Life Mage, a Death Mage, and preferably also a Nature Sniper - they are really great... the funniest heroine in Chaos is the redhead Medusa (she even takes off her wig on the battlefield :))... if you take her at the start, then after a week or two, her copy appears in the tavern... I've defeated so many armies with these twins... oh well... I want to play Heroes IV again...