Which hero is the best in the Tribes of the East expansion?

I think Vaishana is a good secondary hero because of the significant bonus to scouts. In general, I believe that for the Dungeon faction, you shouldn't choose a main hero with a specialization in certain units, because due to their low defense, the enemy can easily deprive you of that specialization in the final battle. The exception might be Kifrah. My choice: Leto, against undead – Sinithar, or Kifrah.