HoMM3 HD is a mod (add-on) for the game Heroes of Might and Magic 3.

[-] (author - Sav) original bugs: excessive castle and neutral zones in Random Map Generation (RMG), crash when removing magical obstacles with a spell, incorrect spell chances for the Dragon spell, failure to reset visited status of map objects, incorrect AI calculation of hero luck when evaluating the value of increasing luck, incorrect wisdom and magic levels for the Elementalist, incorrect display of attack with stack bonuses in combat.
[+] (author - Sav) in player cities, if a fort is present, 2 levels of creatures will always be built, and in neutral cities, 1 level.

Could you elaborate on this (the part in the first section)?

Regarding the second point. Baratorch, this is usually done in a different way. Let's say, like it was done in Warlords Tactics. One or more key individuals come up with the idea, and then they develop a package of gameplay changes. This is then discussed by the community, somehow filtered, and then implemented and tested. If you introduce these changes in small portions, firstly, people will get tired of constantly having to readjust their thinking, because such changes will inevitably affect the game's tactics, and there is a risk that after certain particularly unsuccessful changes, there will be a desire to abandon the new developments.