I would prefer a Jurassic World expansion over anything else for Stages 22-25. That area is ripe for a Visitor Center or the Amber Mines. Maybe even kiddie spinners and a new Raptor Encounter area.
Honestly, and this is going to come across maybe in a bit of a hypocritical way, but would the GP really know of Amber Mines? Not to mention, unless if it's featured in Fallen Kingdom, it wouldn't make practical sense to have Amber Mines featured as an attraction, especially if SNW has Donkey Kong and the Boom Patent.
I would think a Sci-Fi themed land (general Sci-Fi, not centered to just one IP) would be a better pick, as you could then have it be easily flexible to change IP's at any given moment, and that you could include Transformers to that, giving you an easy out to re-theme that building. But that's just my two cents.
There is something everyone is forgetting...that T23D in Orlando was announced that it would be replaced in 2019 with a new show. What is one thing the Lower Lot needs...a show. Something to pull the crowds out of the streets. Could Stages 22-25 become the home to a new theater?
Including 28, that gives them a lot of space to do more than just one show.
I actually don't rule it out, and think that it could make sense (Depending on IP), but that I would think it could work out well.
We have the success of GOTG:MB to thank for this. Hopefully they do a good job.
I'm actually surprised that they didn't have it ready this year for Fallen Kingdom, as that would've made more sense to cross-promote. Either way, I am glad to see JP get the love, as it needs it badly.