Great Tip!!
Here's what I found:
Hiding clothes in CAS.
With Active Sim > City Hall or Computer > MasterController > Settings > CAS > Hide By Packs

Here's one we might be familiar with, but thought I'd share it anyway.
Reducing Clothes Loaded in CAS
With Active Sim > City Hall or Computer > MasterController > Settings > Show in Compact Form: Accessories, Clothing and Hats - Set all of these to True (Defaults to False)
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Neither option is what I was hoping for. -- I though or maybe was hoping for something that can be used in CAS to turn off what clothing/accessories aren't wanted. Or even hide them, like you can hide lots in the in-game library.