Hey,
we are playing a custom modpack with your mods and we encountered an issue where a change of resistances and health (from 200% down to 150% and 100% for example) made the game have really bad UPS issues, dropping us to a whopping 10-20 FPS/UPS.
The game script rendering engine took far too long when not on map overview.
When we changed the values back and loaded the same save, everything was back to normal.
Can you have a look if your mod may have some issues with that or if you can do anything that prevents this from happening?
Cheers Ramses

Sorry for the late response, I'm not sure why thats happening but from some testing I can replicate the behaviour. I guess it might be due to the game now having two versions of the same entity (one set with the old resistances + health and one set with the new values).
If you're still experiencing this issue could you try the "/c game.forces["enemy"].kill_all_units()" console command to see if it helps with UPS?