I havent noticed ANY lowered spawn rate in the swamps, I cant do anything without getting 2-3 draugr and some skeletons together with those always-happy-to-see-me blobs. And I have cleared out most Draugr/Skeleton spawn stones.
Black forest seems sameold too.
Maybe im just lucky , but i try not to plonk a lot of workbenches around, as they inhibit spawns. In my experience Iron Gate is not a dev that gives in to crybabies.

PS My world was created after the H&H update.