What would you change in Heroes of Might and Magic IV?

No, all creatures that you don't mind losing go into battle. And those you care about protect those you don't. The fact that a hero can be killed is better than when the last unit is killed and you lose. But it would be good to remove most of the unnecessary spells that you don't use and replace them with new ones. For example, replace "Walk" with "Swap Places."
The Elder Scrolls 3: Morrowind is definitely a great RPG.