I don't think the new ships are too big, but I do think we've seen the upper limit and they won't get bigger than the Oasis class.
I will return to either the Oasis or the Allure when I can do the full 7 nights with my wife and son. Beyond that, who knows? I want them to experience it. One thing I do want to say is I did feel I was on a ship at sea. I felt the ship's movement in my cabin. I could see the ocean from my window. At night it was serene to sit in Central Park and look upward into the sky. You could tell you were moving and hear the exhaust rumble. I agree with other comments that groups and families should really look at the Oasis or Allure. They would offer an almost perfect choice which has something to satisfy everyone. The big holdback is obviously the high prices. They would kill the average budget for a family get-together cruise.
We've done the Caribbean to death and the ship becomes more of a factor there. None of the ports hold much interest for us anymore. I could easily stay aboard Oasis for the entire 7 days. I just don't think I would want to do it more than a couple times.
Although I think the Norwegian Epic is externally the most homely ship I've ever seen, I am very interested in the entertainment on it and can honestly say it is a cruise I will take because of the ship's shows and music. But once again, it will probably be a one-time cruise, never to return.
I can't say anything about the Carnival Dream. It seems like just an evolution of the Conquest style ships, and I've received some initial reports that the passenger density is high. In other words, it is at the bottom of my list of new ships to try.
I totally love the Solstice class!