Okay, fine, the lack of special abilities is a drawback, but in the same Heroes III, in Tournaments, some heroes are penalized solely because of their special ability. And the progression in Heroes IV is much more interesting – with pure experience, you need 98 levels compared to 24 in Heroes III. And the classes are a great thing.
In my opinion, the most interesting skill system is in Heroes V.
What's the basis for that? Morale is subject to a certain rule: two heroes of different races in the same army incur a morale penalty. I don't remember exactly how it works right now, but if I'm not mistaken, two heroes of neighboring races deduct 2 morale points from each other, and if you add a third hero of a different race from your city to this army, this third hero receives a -5 morale penalty because he will not be adjacent to one of the two initial heroes. And if the races are completely opposite (e.g., undead and life), the penalty is -7, as far as I remember.
And doesn't Heroes III have morale penalties? Explanation for the "experienced player": mixing races always incurs a morale penalty!
This is not important in this game.
In Heroes IV, you can move around the map quite well.
In general, variety, variety, and more variety!!!!!!!