To me, it seems the random starting heroes would not solve anything in the balance issue.
Sure, inferno / fortress / stronghold would become a bit stronger in comparison, but flux would remain top, and necro would not be affected so much as dungeon and rampart. The latter 2 would suffer greatly from this change, quite unnecessarily since neither of them are considered OP in my book. So the question remains, how do we balance flux and necro to match the other towns.
I think, there is a solution to this that could fix the imbanekr in general, not just in pets.
It is a general problem in sod, that necro heroes are too favorable in comparison to others, with any town. Just for example, from the 5 games we played with Bishop in previous pets, 2 games were necro vs necro, 2 games were necro vs dungeon hero (both times necro won), and only 1 game was barb vs dungeon hero, on mt_diamond. From 23 games, I mained necro 8 times, that's pretty high, considering I had gunnar with me most of the time.
We consider thant and galthran imba, I can agree with that.
If we were to copy the mechanism from Isra / Vidomina to all necro heroes, it could weaken them enough not to make almost every game a roll for necro or restart. Halting necromancy at advanced level until all other skills are maxed out. We could even lift the ban on galthran, and necropolis would remain a strong town, but with other castles, maining a non-necro hero would be more favorable.
Everyone can still pick their favorite heroes in pair with their favorite town, and we get to enjoy a wider variety of hero types. If we just go with random heroes as it is, the tourney becomes a big necro fest.
About the ban of tower library, I absolutely oppose it. It makes no sense to ban the biggest strength of a mostly average town. If enemy has view earth, he can easily identify where tower is and steal it. Also, control from guild is mostly OP when it comes on the first or second roll, so library is not really imba here, IMHO.