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

This isn't spam; it's a litRPG. I played the "Whirlwinds of War" campaign. The artifacts weren't used, probably because they rushed the development. But the AI is just great. Five heroes show up without troops and just wipe out my overpowered hero with immortality bubbles and all his troops. Maybe it's because I was playing on the Equilibrium mod, but the campaign is unpassable on Champion difficulty. Interestingly, the first two maps are passable. But in the third, even a well-leveled hero gets killed, and reloading doesn't help. I'll keep playing, but I've already tweaked it a bit, adding artifacts and various buildings, and I'll post it here later. I also made artifact transfer possible between maps, as it wasn't available at all.