Please, make it so heroes are immune to conversion! Losing a hero to a priest can mean defeat in certain scenarios. The “science” behind this is that they would have a much stronger will and ideology than any other regular unit, hence making them immune.
The worst of converting the hero is that the game continues. You should at least be defeated when they convert the hero.
I have converted Hector in Trojan war and let enemy units or towers to kill it and after that received victory.
You could have just pressed delete.
I know, but it was funnier let enemy killed their own hero.