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

Your vision of the game is clear. But what you described isn't balance. It's a lot of different elements that make up the gameplay.

Removing one-way paths won't suddenly make the game perfectly balanced (and it doesn't seem like anyone is claiming it will), but it will make it more playable on maps where there's too much of it (8x12, 6LM10).

For me personally, the problem was solved with 8MM6B, although I haven't played it much yet. And those who want to "win" by having a clear path to a one-way area can go for it. But predictably, they'll end up playing only with CMs and Jebus.