Never did MSC. Like you have been in all types of cabins on Celebrity, except PH. Including Aqua (meh). I have a close nephew and his spouse trying MSC Yacht club. They have tried most cruise lines and cruise at least 6 times a year- Waiting for his review.
IMO if you ever sail on NCL also like you said about the Yacht Club- either the Haven or skip the cruise. We enjoyed the Summit, M-class , Solstice class ships and three times Edge class. Loved it.