I feel like when everything is set following the opening of MMRR and Galaxy's Edge, DHS is certainly going to have enough to fill a whole day. There are going to be 6 Rope Drop worthy attractions (MMRR, Falcon, Battle Escape, TSM, RnRc, ToT), and it will take a good chunk of time to do all of them.
Then after those are done there will finally be filler attractions that aren't as flashy when it comes to marketing the park, but are just as important for park flow and keeping parkgoers busy. These include Slinky, Aliens, Star Tours, Muppets, and a load of theatre shows that, old or not, have a healthy history of good reviews and satisfying the public.
And this is all without the potential addition of an Indy E-ticket to Echo Lake. It's not everything we wished and hoped for, But its gonna be one heck of a good time to spend a day at this park come late 2019.