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

But isn't the market in the 4th game very cheap, allowing you to ignore some of its shortcomings?

In the 4th game, clearing the map still happens in 1, at most 2 directions. It's impossible to cover the entire map. (I'm talking about the classic online mode). Therefore, this is a perfectly harmonious simplification.

That's the point. You can't get enough level 1 units.

I find it hard to imagine, considering the general principles of development...

Great, so you can have battles that last 20 minutes. Deliberately slowing things down, throwing arrows and casting spells.

This is actually the case in any part of the Heroes series. In the 3rd, 4th, and 5th games, it's definitely a common occurrence.
For example, in the 4th game, every long battle was always enjoyable for me. They turned out to be important and challenging, and therefore very intense. Often, it was a close call.

+ it also forces you to carry a mage with you.

If you're playing with just one hero, then everything falls into place :)

yes, but if you're playing a strength-based build, you can hire an Ogre in equipment and get the first strike.

Only against birds, but very rarely