Ideas and suggestions.

Vampire lairs in the Hot area have a value that is 3 times higher in the GSC. If there is only 1 Necropolis zone on the map, its value will be approximately 8000; if there are 2, it will be 9000 (like a relic), and so on, approximately 1000 value per Necropolis zone. Because of this, they are less likely to be found on spawn points of template maps like 8mm6a (since they only fall into the upper range of 10000-15000, and there are few objects in that range generated on spawn points), and they are quite well-guarded; moreover, again, because the lair falls into the 10000-15000 range, even with a value of 8000, there is a high probability that the lair will be generated along with a couple of resource piles or similar, which will affect its protection.