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

Why is it necessary to take level 3? And always. Djinns, Vampires, Crusaders – they never spoil the picture. ;)
As for levels 2 and 1, it's just cannon fodder, and cannon fodder is overcome with numbers. Don't lose your Berserkers and unleash them on the Chaos Dragon at the end of the game. And then level 1 will be stronger than level 4. ;)
But using levels like in Heroes 3 (Heroes 5) when the difference is minimal from level 1 to level 4 is foolish. And adding upgrades on top of that. In Heroes 2, the level spread and castle balance were optimal. IMHO.

I don't have anything against spells... It's just that there are too many variations of the same action. Let's say, how many types of slow spells are there in Heroes 4????? I've even lost count... Why not have one, but with a greater effect????

This simply speaks to the player's skill level. If you're facing Berserkers and Harpies, using a mass slow spell will lead to losses, but you need to use a targeted spell on the Berserkers. That's it. Not to mention when you have a mass dispel, but your creatures are individually cursed. Then the dispel will work against you. ;) Spells and their breakdown in Heroes 4 are ideal:cool:

Then you would have to change the magic system. Then level 4 in life magic would be useless.

You forgot about Prayer. ;)
And in general, unlike Heroes 3, in Heroes 4, the price of each specific level has increased, while in Heroes 3, only every third level makes sense, and in Heroes 5, with its skill system (more than 80% of which are absolutely unnecessary), it's every 5th level, if not more:eek: Where's the game?

I'm done with the off-topic discussion:D And in general, my favorite are the second Heroes games (Heroes 4 is in second place)