I've noticed a lot of trends in the comments here that I find odd. Taking Frozen entirely out of the conversation, there seems to be many who feel that World Showcase is not a place for "the kiddies" or at least not for any large amount of them.
Oh, it should certainly appeal to all ages. I find that stance very odd too. Should Epcot really only be for adults? No, not at all. While Epcot can continue to be educational, it should certainly provide a fun day for youngsters.
There are plenty of ways to do this. The land pavillion, particularly Soarin, is the best example. Soarin appeals to almost all ages. It's a fun ride that shows different parts of... well... soon the whole world. Not boring for kids, not boring for adults. It's not "preachingly" educational, but it does subtly educate you without you even knowing. It's a great fit for Epcot.
Children enjoy looking at the plants in Living with the Land. I've changed my thought on The Seas a bit, becuase nemo might get kids interested in the aquarium stuff after the ride (though it's completely hypocritical that Nemo is promoting an aquarium but whatevs). Test Track did this great before the redo, now it does alright. Mission Space gives a feel of being an astronaut. Everything else does sort of alright. Not great, but better than the original rides. I think the originals were excellent, but to keep children interested, a bit of the "preaching" aspect needs to be substitued for some flare.
And Spaceship Earth, well, I think having a centerpiece ride like that is fine. There's something about it that you don't appreciate till you're older, and while I hate to sound hypocritical, it's okay to have one or two rides like that.
Anyway, my whole point is that the idea of Epcot isn't dead or impossible, it just needs to appeal to all audiences. So my concern is that Frozenstrom won't at all have this balance I talked about. It seems almost completely tipped toward just being fun or magical. And that's what Magic Kingdom is suposed to do. That's my concern, the ride will be out of balance. I hope I'm wrong.