I believe the game will read mods up to four levels down, but I don't remember if Packages counts as the first level or not.
If you have a bunch of different sets of cc for different saves, you might want to just create separate game folders to go with them. That way, you don't have to keep track of which sliders or other cc files belong in which save, or worry about a townie sim being "exposed" to some cc without your knowledge and then getting borked when you later remove that file. (Normally, the game just replaces a cc item, but I'm not familiar enough with sliders specifically to say how removing them would affect a sim that already had them in place.) Separate folders would also make it easier to navigate CAS and Build/Buy, since you'd have far fewer items to sort through.
