Thanks to both, you're so nice!
So here's what I've tried so far:
-Tweaking graphics settings.
-Deleting parking lots from community lots.
-Cleaning inventories.
-Cleaning caches and FeaturedObjects folder (I set it to Read Only too)
-I always play with memories, pets, celebrities, vampires and interactive screens disabled. Rain and hail are also disabled as I find they slow down my game.
-Deleting older save-files.
I just installed the game a couple of weeks ago so I don't think a Factory Reset will help much. I will try it as a last resource though. Right now I'm downloading Error Trap and Overwatch and crossing my fingers. It's pretty unplayable at times, with freezes every 2-3 sim-hours lasting for at least 30 seconds real time. I also has a crash yesterday, which hadn't happened before. I've been playing again today and it hasn't crashed again though. I'm pretty sure this is caused by a a pathing issue since resetting town does help for a while. Someone in the second thread MrsFlyn suggested mentioned that a family in IP has a horse with pathing issues. I might try to find it. IP is my favorite world and I would hate to stop playing in it. If the mods don't work I think I will try the custom version from MTS.