How to achieve Balance?????

Balance? Are you talking about a skill set for navigating the dark dungeon? It seems that Elemental Balance can be found in the skillwheel program, which is installed in the FanDocuments folder in the directory where the HoMM_V game is installed.

Cool map, I defeated the Devil and Death, but I have a question: is it impossible to hire Titans?

Added 2 minutes later
And another question: in the desert, there are gates to the right of the Shaharadia city. Will a super-invincible enemy appear there later, or are they just for decoration?

Titans can be obtained by completing a quest for the prophet in the Orcish lands.
Currently, the eastern city gates are simply for decoration. There is just a sign with the name of the eastern lands behind them. This was done more to support the map's plot - in which Shaharadia is surrounded by other states on all sides. But all of this couldn't fit on the map, unfortunately.

Thank you for the kind feedback.