I think its really obvious that it's going to replace Kidzone and possibly ET. Curious George, Woody Woodpecker, Barney...none of these are relevant anymore. Also I think Jaws was considered more of a classic attraction than ET but that didn't stop it from being replaced with Harry Potter. Speaking of Harry Potter, seems like what's left of Lost Continent is prime expansion space for that franchise.
In a strange way, the current management of Universal sort of reminds me of Premier/Six Flags in the early 2000's. They are really building some great stuff, but are operating their parks poorly from a guest perspective. However, the difference is that Universal has been financially successful, while Premier/Six Flags expanded their parks in such a way that bankrupted the company, closed the largest amusement park in the world (Geauga Lake), and turn some parks into shadows of their former self (Elitch Gardens).
I have to disagree with you bigtime here. The metal detector/l*cker situation is an annoyance but running 1 train on the most popular rides (if open at all) during busy times of year is much more of an annoyance. Also Universal as far as I know fully staffs its third shift maintenance and custodial, and the rides have very little downtime.
Six Flags those days you never knew what rides were going to closed, late opening, running 1 train, down for staffing, etc. Universal Orlando's operations are probably just as good if not better now than ever.