Game crashes sometimes, I can't find the broken cc +fps drop

Hi.
Start by disabling all mods and scripts to see if it is caused by them( while youre at it, set graphics settings to the lowest to speed up the process). If the issue persists even without mods, repair the game
If the issue is indeed caused by mods, try Better exceptions by Twistedmexi
If with any family you tried so far, try loading a maxis family that wears no cc at all. If it will still happen, it is probably some type of gameplay/UI altering mod or a replacement
If with a specific one, find every cc they are wearing and delete it. If this wont help, try moving them in a different lot (that has nothing in it). If the issue will disappear, some furniture in that lot is causing it
If none of this will help, 50/50 is your only way