Pretty noncommittal offerings at DAK. I will be curious to see how this does at DHS, especially, where I don't think it's needed. I bet it's moreso a test for 13 months from now when it'll include Star Wars Land, which people will surely pay $125 (or more!) for 3 hours in.
This sounds like a huge waste of money. A half-empty, but half closed park. The only positive I can think of is to get on a particular attraction you couldn't get a fastpass for. I wonder if any restaurants will serve non-ticketed guests who just want to hang out.
I've done the Magic Kingdom event a couple of times. It's not as empty as the bloggers on youtube make it seem. Some rides are a walk on some are not. On both of my after hours, The 7 dwarfs mine train was still 20+ minutes, and Peter Pan's Flight and Space Mountain had small waits.
We did the MK After Hours event and loved it this past summer, the kids said they would rather do 1 or 2 of those events in a week then 4 regular days. Price ends up the same, more pool time and a better experience.
I don't know about the lack of attractions at AK. Once Galaxy's Edge opens I would pay in a heart beat but assume that it will never be offered as an After Hours event at that point but some special event that will cost even more.