We used to be a family that traveled without children to WDW, and now we're a family that travels with young children. We're DVC members and go once or twice a year almost every year, so both my kids have been to WDW many times. The 2 year old already has a few preferences, and the 8 year old has strong preferences.
My kids don't really like DHS much, and DS regularly encourages us to skip it. The only things the kids really enjoy at DHS are the Honey, I Shrunk the Kids Playground (although they have never seen or heard of the movie it was based on), Disney Junior on Stage (DS has mostly outgrown it, but he will go along and sing with it to encourage his sister, and I think he secretly still enjoys it a bit), and TSM (which we really don't do often because the fast passes are generally gone by the time we make it there.) DD likes the Voyage of the Little Mermaid, but DS really doesn't. DS likes drawing with the animator in the animation exhibit, but DD isn't able to do it yet. So, basically, there is very little we enjoy as a family there. We skipped DHS entirely on our last two trips. Cars Land or an expanded Pixar area would have gotten us in the gate. Both my kids would enjoy that, and I suspect DH and I would as well. Star Wars Land will be a draw for us, and we can't wait to see what they do with it. I hope they do it justice. Until they do something new, we're probably going to skip it any trip where we don't have annual passes. It just isn't worth the time or money to us in its current state, except maybe during the holiday season to see the Osborne Lights.
My kids are both animal lovers, so we usually spend a fair amount of time at AK. We enjoy the animals enough that we find enough to do every trip, and my kids both absolutely adore the Boneyard. We don't mind the park in its current state. I can see why many people think of it as a half day park, and why it could use more attractions, but, for us, it is still a must do. If Avatarland happens, we'll probably find things to enjoy about it, too.
Epcot used to be our favorite park. We practically have to drag our kids there, except, surprisingly during the Flower and Garden Festival. (We love Food and Wine, of course, but our kids barely put up with trailing Mom and Dad from booth to booth, and would rather be back at the resort pool.) The Flower and Garden Festival adds not only the stunning topiaries, which my kids enjoy, but also interesting playgrounds. Sure, there are a few things the kids enjoy year round (The Seas with Nemo and The Land pavilions,) but Epcot isn't a favorite with our younger generation. I loved Epcot as a kid, and I'm certainly let down by what it has become. I'd like to see another international pavilion or 3 added, but I'd really love to see them improve the Imagination Pavilion (which it looks like may be happening) and do something with the Horizons and the Wonders of Life pavilions.
I'm not surprised the Magic Kingdom is far more crowded than the other parks right now. On our most recent trip, my kids kept asking for more time in the Magic Kingdom. While I know some are less than thrilled with New Fantasyland, my kids both were excited by the Tangled bathroom and rest area, the Beauty and the Beast area, and the new Little Mermaid queue and ride. (They did not care for the new circus area and couldn't wait to leave it, however.) The kids enjoyed doing their old favorites, and found the new additions magical. We spent more time in the MK last trip than we ever have on any of our previous trips. (Admittedly, part of this is because DD is into princesses now, and has learned to voice her opinions frequently and vocally.)
If my kids could plot the perfect WDW trip right now, it would be something like 2 hours in DHS, 4 hours in Epcot (except during the Flower and Garden Festival, when they will gladly spend all day, and maybe even 2 days), a day or two in AK, and 2 or 3 days in MK. If DH and I were doing it without the kids, it would be more like 4 hours in DHS, 1 day in Epcot (except during Food & Wine, where it would be 5 nights in Epcot

), 1 day in AK, and maybe 4 hours in MK. We all seem to enjoy spending more time in the resorts now.