:!: Edit to highlight two VERY easy fixes:
Remove the house the medina family lives in.
Remove the house the Amigos live in.
You can move the sims in both families to other houses, they are ok. :!:
:!: :!: Do NOT delete these premade simmies! Move them all in other houses, but do NOT DELETE :!: :!:
If your lag is the result of sims getting stuck this should improve things a lot. Maybe then the rest of the thread will help solving the last little laggy bits
I decided to give it a try:
I redid all houses in IP.
Removed some of the hideous modern ones (like the one the alto's (?) live in) and some of the houseboats.
I fixed front doors and lot fronts of all the lots. ( alot of the the houses had their front door set inside the house! (example the house where the collins live and the adobe abode)
In a lot of the houses, the toilets were in front of the showers/baths, so they were unroutable. (the houseboat where rubisel ichtaca lives)
I also put some rocks where al the npc's got stuck near the premium port.
It took me about 3 reallife days! (am not a great builder), but in my modfree new game there is hardly any lag anymore. Only when the game is building the festival lot it stalls a bit.
* makes happy dance *
Try it, it really did wonders for my game!
I tested in the rebuilt town for about three simweeks.
I thinks the lag would've started in that time
but it didn't.
and I'm still on patch 1.65, if it matters.