OK I'm back... so I researched this topic before going on the Wonder because I had the same concerns... so a few random thoughts:
- I found the biggest difference was the atrium, definitely a smaller version, a smaller feel right away when stepping onto the Wonder so for this reason I googled the videos and images of the atrium so I was prepared for the difference, instead of it hitting me without expecting it... once I did that I felt I still could have the magic of entering the ship with the grand atrium
- I had a previously booked 2016 EC cruise on the Fantasy heading into the Wonder 2015 cruise, after snagging a cabana as a silver member on the Wonder (just got lucky from stalking the port activities
DCL website) and seeing how no magic or experience was lost - I went to on board reservations and changed my booking to 2016 EC cruise sailing to the Magic instead of the Fantasy for my 2016 cruise - this was confirmation in my opinion of how both experiences are awesome but I wasn't sure until I saw it for myself (happy I did because I was able to snag a cabana again!)
- I was comforted by the size of the restaurants, they were much smaller than the bigger ships and I noticed their size but it just served as a reminder of the lower headcount on the smaller ship, more of an tight knit feeling
- the dance party is much smaller and crowded and better on the bigger ships imo
- the pools! the pools are way better on the smaller ships, especially love the new set up on the magic... I was blown away by the adult section compared to the Dream - I haven't experience S Falls yet so I may change this after my cruise next year but I was really impressed by the pools and the pool crowds, it didn't even bother me to be at sea with the crowd sizes
- the pirate show - so much better imo on the Dream... I don't like the rock and roll party on the older ships and love the longer time devoted to the characters and songs on the Dream
- we didn't experience mid ship detective because my kids were too small so I didn't feel like I was missing anything for that reason but looking forward to it for next year
- service - I feel like Wonder was the best, Dream was the second best, and Magic was not as great but OK
- night club - hands down better experience on the Dream but the adult clubs on the smaller ships are still great - we aren't night out people anyways, we usually drop the kids at the club after dinner and have an after dinner drink and thats it
- Rapunzel! Best show ever (on the Magic)
After I go on the Dream next year will be happy to update but I really enjoy the smaller ships - different experience but still enjoyable. Have fun!