Looks like this is the only suggestion, the others are questions, but in keeping with old traditions - I'd like to suggest:
That SC introduce ways and means of using SCBLs under cPanel accounts. A tool so we can drop in SCRBL s and let cPanel compare incoming mail to SCRBLs, and delete the often very obvious spam.
Yes. Thanks for suggesting spam Assassin. If it was reliable, I wouldn't be suggesting side stepping the etch-a-sketch version of dealing with spam to using SC block lists instead of SA.
O