increased tick per mob spawn to 400 rather then 40. This will make guardian farms spawn guardians slower in turn reducing lag without destroying farms.
Set a limit for villagers per chunk to 6. This has noticeably decreased lag already.
Mob farm limits adjusted to the following. This makes it so no more then the number next to the mob type below can be in the same chunk. If the number is exceded it will automatically purge those mobs.