If the event is attracting significantly larger crowds and spending every year, it's reasonable to expect that Universal will increase the budget & expand their offerings. A second show, 10 houses, and more rides open, would be a reasonable expectation for 2019.
Not only is that a reasonable expectation, I think it will be a mandate based on the crowds this year. The decision not to go this year was pretty easy based on our experience last year, with ridiculous crowds that only an express pass would have alleviated. After randomly jumping on the app to check wait times this year, our decision was confirmed. You either need several nights, express pass, or both to enjoy this event any longer, at least in my eyes.