I think there needs to be a balance and the first four do a better job at that.
There is no doubt you are with Disney. Characters are everywhere, there are Disney references, music in common areas, etc. However, it doesn't feel like a real life Disney commercial and it's done in a way that isn't too overpowering. You can get away from that easily if you want to.
On the Wish, it's all Disney all the time, or so it seems. IP's are everywhere and they make no mistake about it. I think this is the way the company as a whole is going. Which I get from a business perspective, but it might turn off some people, especially on the cruise line.