I would have to say w.i.t.c.h, they are much easier to interact with,and are favoured kwa the animators, plus wewe can relate to them zaidi because they're kids with the same promblems as some children today example: Will's mum is divorced, Taranee having a over protective mum, in the comic Haylin's grandmother dying etc. The last generation of guardians however, don't have enough screen time to get use too, thus unrelatible, but it's just my oppinion.
I like both of them.I like W.I.T.C.H cause of they're great firendship and know how to work together and I like C.H.Y.K.N cause the have mad skills and awesome outfits.