Couple of things to keep in mind when using CC

Every time you put in new CC or remove it go to your main Sims 4 folder. Delete the following package and text files: avatarcache.package, clientDB.package, localthumbcache.package, and any of the following Text documents: Config.log, ConnectionStatus.txt, GameVersion.txt, and any from the mods you use. I get ones from WonderfulWhimsInfoLog.log for example and sometimes Exceptions from MccCommand.

Next, go into the yellow folder that says Cache. Select all and delete. This folder is basically a reservoir of images that do not need to be there, and it will fill up and cause lag if not cleaned periodically.

Another tip is your screenshot folder. Screenshots are great but can make your game lag over time. Create another folder somewhere and copy/paste or cut/paste them into the new folder. Delete the ones in The Sims 4 Screenshot folder.