Ideas and suggestions.

The fact that harpies can capture current structures (with a speed of 6) within 100 rounds is well-known. Furthermore, I believe it is important that one of the rules (in the event of a stalemate, the attacker must retreat) is now technically implemented. I understand that in some cases, this changes the gameplay, but I don't consider it a major sacrifice. Yes, now the attacker may sometimes have to retreat in a non-stalemate situation if they don't manage to trigger morale. However, the Necropolis and Graveyard are essentially free structures, and I don't think it's a problem that they will become less free, meaning that, along with the Angel for reliability, single-unit creatures or similar will be needed. It should be noted that the 100-round limit, as well as diplomacy with the Laboratory, can be disabled in the template editor. You can also change the number of rounds there.