Following up on some of the ideas included by
@UniversalRBLX, plus others, it does look like a Wave Swinger could fit where suggested. The manufacturer calls for a 21 meter diameter area and based on what I can tell from Atlantic (~30m diameter) there is space. It may want to be on an elevated platform with a shady queue underneath.
I also think a 13,000 sq. ft. Fantasyland-style dark ride could fit adjacent to Pizza Moon (for comparison, Peter Pan's Flight at Disneyland is just over 9,000 sq. ft.).
In Dark Universe, a couple of enhancements could include an outdoor stage performance area where some of the backstage parking lot is. While smaller than the show they were exploring, it could be a comparable area to the performance area in Celestial Park, with a Mystics camp feel (shaded with canopies), and be a great place for Dark Universe theatrical storytelling.
A walk-through catacomb experience with jump scares would fit in nicely between Curse of the Werewolf and Darkmoor, and satisfy horror fans that want some "do you dare?" level scares.
I also think a new "final scene" for Curse of the Werewolf, flipped to the other side of the track for more space, and with an elongated entrance to allow low-light-level control, could really boost this attraction's value for a modest investment.
Finally, for Ministry of Magic. Here's a possible layout on an area that includes a flying carriage dark ride (journey from Paris to NYC), with a 1920s wizarding Times Square street/plaza. Forced perspective buildings at the top-rear of the show building would create the illusion of a full NYC skyline. An exit gift shop and NYC diner (burgers, shakes, sundaes) would fill out this world extension. A discreet tunnel passage would lead back into Wizarding Paris.
And for how this Times Square could look, here's some reference images:
