Ideas and suggestions.

Suggestion: introduce an additional requirement for building a vampire upgrade – GM level 2.

Hmm. And why? Right now, Necropolis is strong precisely because at level 121, they can build and buy lords, and even if things weren't great financially in the beginning, they can start the second week by quickly destroying objects. This compensates for some of the difficulties of the first week and the lack of a large number of skeletons. At level 122, this no longer looks like a significant bonus, as most castles are capable of managing this right after the growth appears.