I’ve never been in a secret military lab conducting genetic research protected by automated turrets, nor an actual mansion. Yet both are more common than gas stations in a city (easier to find too).
Current default settings spawn a stupendous amount of 0-60 labs and 0-24 mansions per overmap. A size 4 small-medium city in dda spawns like ~30 buildings. When you spawn 60 labs on the overmap, that’s equivalent to having a secret underground lab for every building in 2x cities (which would be hundreds upon hundreds of labs in real life).
Realism aside, it’s just horrible gameplay due to excess repetition. Who wants to explore 10 labs followed by 7 mansions in a row? Both specials contain mid/endgame gear and the player literally can’t go in any direction without burnout-level inducing spam of labs and mansions. This in turn forces the player to nuke his drop rate to 0.05 or alter overmap_specials.json to maintain any kind challenge or fun.
Good settings would be 0-4 labs outside cities without road connection (they’re secret labs after all), 0-2 labs within 0-1 distance of a size 7-9+ city, and every mansion reduced to 0-1 chance and further segregated by city size to prevent one city spawning 5x mansions.
The mainline branch desperately needs to take some influence from mods like overmap rebalancing and pk rebalance.