If you are doing the W2 route then that is Whytes Level and the Wall trail combined so on Sunday you could do whichever one is your favourite and then hit Cwm Carn on the way home.
I love Whytes Level but the final decent on the Wall is great and the new bike park at the top of the wall is great fun even for mere mortals like me so defo stop off have some food at the cafe and do some laps there.
Never done Skyline at Afan as that is the longest route there so may be worth talking to people at the centre to see if it is worth doing.
If you are camping at the new centre then beware of midges/flies/insect beasties etc. it may not be warm enough for them yet but they are lethal if they take a liking to you!!!