(raising my hand, wiggling in my seat) I can answer that!!
We were on Magic this summer and Wonder over Christmas. First off, Wonder is in great shape. No worries there. I actually like the overall styling better on Wonder. There is a really nice adult only bar/coffee bar over the Cove Cafe only on Wonder, with great views. I would have lived in it on Magic (if it existed there), which was a longer cruise for us with more down time. It is WAY better than just the Cove Cafe on Magic, which seemed impersonal and drafty. I personally liked the adult only lounges on Wonder more also, especially the Cadillac lounge, which is a really classy piano bar. And honestly, we spent very little time in either, these spaces just left an impression. We had verandah rooms both times. The rooms are almost identical, with the exception that Magic had dressers with drawers and Wonder had a steamer trunk-on-end sort of contraption with one large door and shelves inside. There is no large slide on Wonder. Not sure how old your kids are. Vibe was identical. Edge was identical. Oceaneer's Lab was much darker, almost with a dance club vibe, on Wonder. I didn't look at Oceaneer's club. (perhaps I have them reversed - the "older" kid one is dark, the "younger" we didn't use.) Animator's Palette was better on Magic, as far as the wall show goes. I actually liked the "old" colors of Parrot Cay on Wonder over the restyled Carioca's. I did not love the buffet setup at Beach Blanket Buffet - too much like a school cafeteria, though the food was basically identical , and good, to Cabana's. I do think our servers were better on Magic, but I think part of that was the shorter cruise on Wonder, and part may be due to
DCL-wide changes in staffing duties from what I've read, so that might have affected Magic now also. Wonder has a secret aft sundeck on 7. Magic does not. Our stateroom attendant was great on both.
Overall, I really liked Wonder over the Magic and would cruise her again in a heartbeat.