,
In my opinion, this isn't entirely correct. Why limit the game? I think it's best to adhere to the principle: everything should be allowed that isn't prohibited.

There are too many restrictions on heroes, which makes the game less enjoyable. Mages, who are powerful in the early game, are significantly weakened. It's a real problem.

Let me try to express my humble opinion:
Mulich should not be higher than level 3 (because he's really overpowered).
Isthar and Vidomina (specialists in necromancy) should not have their necromancy skill raised to expert level; otherwise, it becomes difficult to play them, and you have to take all skills. Also, necromancers shouldn't build the enhancement.
All magic specialists (levels 2-4) should use magic against opponents after building the corresponding level, finding the relevant spell in the Pandora or spellbook. Let the mages develop...
Start with Necropolis and Conflux with a random hero, and then it's all about luck: who you get, who you find, there are many development options.

You calculate how much damage Ciel deals, and that's fine if she appears with a random hero, because if air units haven't been built and a second hero hasn't arrived (which often happens), how can you fight 50 butterflies when there's no blessing in the tower, and you need to defeat 80 zombies or shooters? That's when you can start with Conflux thanks to this ranged attack.

Fewer restrictions, except for reasonable ones, and let the battles begin!
Good luck with your games, best regards, Vitaly