Could Universal build and open a second waterpark at the same time as CitiWalk 2.0, hotels, and the 3rd park? It could help Volcano Bay's capacity issues, and make Universal South into more of a resort destination.
Also, it would be kind of nice to not have CitiWalk 2.0 connect directly to the 3rd park. Build a Hogwarts-Express-like transportation system to carry guests to and from the park, with buses and a long walkway just in case the train breaks down.