And I will yet again reiterate that Universal used to have absolutely amazing shows with fantastic production values or simply funny/original/interactive shows. It's not all about having a popular IP library. Universal was able to captivate audiences with great shows in the past, and I'm sure they'd be able to again if they structured them differently.
And honestly, the "Disney is primarily for younger children" mentality is dumb. The decades and generations of popularity that Disney has with different age groups (not just harbored D23 attending fans) is astounding. Universal slowly but surely needs to create timeless experiences. They have the power. All it takes is the flick of a wand.
"In the past" though.
Yes, for a long time Universal had captivated audiences with their primary means of entertainment being shows. The Upper Lot at a time was nothing BUT shows, GOOD shows even original. But as time goes on, those shows become stale as the next generation deviate away to a different form of entertainment. See, what you need to remember is this is a MOVIE park. IP is hugely important because it draws crowds, Potter being a HUGE example. I get what your saying though, and it could be easy as a flick of a wand but the irony about that is
they don't use pixie dust.
See, what you don't get when I talked about "families with younger children" is that is the biggest demographic of theme park visitors. Disneyland is by no means a "kids park" but in terms of show entertainment, they have to contend to that demographic. They utilize their IP library because that's the biggest draw, and it's pretty powerful. I mean, there's a singalong show of Frozen RIGHT NOW that is probably the cheapest show in Disney's attractions. It's easily gets a full house.
Universal strength relies on 12+ audience (For now). There's a different mindset. They want the "cool rides" and "immersive worlds" not just anything "Frozen." So as much as I understand what you want from Universal, I truly believe Universal is way past that time era where shows can put "ass in seats" as a permanent attraction, no matter how good it is or how much money they put into it. Waterworld, as entertaining as it is is getting it's boot soon.
BUT
There are timeless shows in Universal's arsenal to take consideration: Bill and Ted's and How the Grinch Stole Christmas. But the smart aspect is they are seasonal. Great entertainment but also a traditional aspect to their season.