How to identify which mod is broken

I downloaded many CC from 17k mods to 8k mods , the game is finally partially back to normal but sometimes the game still freezes even though i already cleared out the custom content that i don't need anymore. I just got this new Better Exception Report that I don't understand. Even if i put the file in lastexception.com report , It says unknown error. I also don't know how to fix my lagging issue when i go to my build mode , it just started to lag so bad even though i don't have any build buy cc. I really need some help ASAP. I want my sims 4 gameplay go smooth like it used to