Given the success of Carsland, I would think that the next big land project will aim for a similar level of detail. I actually just rode all of the rides in Carsland, and while they are fun rides (Mater was a lot more fun than one would have guessed given online comments, and Luigi's was easy to get a hang of), the icing on the cake is that just walking around Carsland is an attraction itself.
I don't think they will duplicate Carsland at DHS, if only because giving DCA this awesome and unique land means that you can only go to DCA to experience it. There are foreign travelers who will want to see Carsland, but also plan a trip to WDW at some point, so by keeping Carsland unique, it helps DLR.
I had a great experience years ago walking around Bedrock City in Arizona, a podunk little amusement park with a smattering of recreations of things from the Flintstones. In a couple years, Pixar will be coming out with "The Good Dinosaur", and because it is Pixar, and because kids don't ever tire of dinosaurs, I think this movie will be a big success (likely bigger than Cars) could be used as the starting point for a land.
The Good Dinosaur will be based around the concept of what if dinosaurs never became extinct and they lived peacefully among humans. As opposed to Radiator Springs, where there are no humans, the city in Good Dinosaur will be built to accomodate both humans and dinosaurs. Big cars for dinosaurs, restaurants with an oversized section for the larger dinosaurs, and a smaller section for the humans, a daycare center for both dinosaurs and baby humans . . . its an interesting concept, and not too far off from the Flintstones, though we aren't talking prehistoric times with the Good Dinosaur.
Imagine entering a restaurant and eating your food while watching these gigantic dinosaur heads and necks poking into the next "room" while they talk about their day at work, "Hey Marge, I think those humans are staring at us! Go back to eating your kelp Frank . . . "
Or riding a ride where your hang glider instructor is a pterodactyl and your are dangling underneath him, or imagine a water ride where you see a beach with a gigantic brontosaurus lifeguard is pulling a human out of the water?
Like Carsland, a Dinosaurland will be an instantly understood a place where dinosaurs and humans live, and the rides could have this great synergy with the environment.
Below is a picture of Bedrock City, very much below the sophistication of Disney attractions, but what is right about the place is that there is a lot of space (maybe too much!), but you don't feel crowded in like you do in some parts of Disneyland. Similarly in Carsland, the rockwork really gives you a feel that there is a lot of space (especially with the forced perspective paint job on the Cadillac Mountain Range), and I think this feel of openess enhances the guest experience.
Should they do a Dinosaurland, I think that this feeling of openess could be used to create a land which has that "wow" factor when you enter it.
New Iguanodon
Population: 1,214 dinosaurs, 223 humans.