With a family of 4, I like that NCL Haven has a 2 bedroom option -- I wish YC had something similar.
YC prices are better than Haven (but starting to catch up -- too many people liking it I guess -- supply/demand), so I pick YC.
Food -- subjective -- my friends like the Haven food better than YC, even though the menu doesn't change.
I like that I don't need to show them my ship card everytime I need to get a drink (haven't been in haven for a while, so not sure if that changed). Plus my kids drinks are also included.
I love the lounge that overlooks the front of the ship and the pool deck bar/food area.
Try it -- you might just like it -- we have, so that's my my last cruises have been on MSC YC.