Hey now, HS happens to be my favorite of the parks!! You've got Tower of Terror, Rock n Roller Coaster, Star Tours, Toy Story Midway Mania, Voyage of the Little Mermaid, Beauty and the Beast, Indiana Jones, Frozen Sing Along...all of my favorite movies and TV shows (huge Twilight Zone fan) done as great rides or shows, plus there are some great places to eat (Prime Time and Sci-Fi are my personal favorites).
Oh, and then there's Great Movie Ride. I was actually quite unimpressed last year. It's gotten a bit stale. My vote is to simply update it, and not just because you have movies that are older. Think about what has come out since 1989 and how it has made an impact on our society. Sure, some movies are timeless classics, but our culture has been impacted in so many ways since 1989 in terms of cinema.
The ride is a classic, but it's time for an improvement to be made. As much as I dislike the idea of GOTG anywhere on Disney property, I'd rather see it at Epcot or Great Movie Ride than taking over my beloved Tower of Terror. If they want to put Guardians there, fine. However, I think Mickey is a much better idea.
Actually, why not do Disney films in general? Have Mickey start it off and make him the host. Go through the rise of Disney cartoons. You can even get Oswald in there if you want!! Then, move on to Snow White and go through some of the animated films/partially animated films. Mary Poppins is the one which needs to stay from the current GMR. Keep moving on up through Frozen (skip the Pixars, keep this just mainline Disney...Pixar can go in the Toy Story area). Then, make the last area the "movie du jour".
By "movie du jour"...let's face it, something like Moana is probably going to be forgotten in a few years. Does anyone here really remember Brother Bear or Home on the Range? Even something like Hunchback of Notre Dame isn't really remembered much. Nobody even talks about High School Musical anymore! Use that space for a rotating exhibit on something new until another Frozen comes along. (Frozen is probably the best since Mulan, and it has the most staying power since Lion King...which ensures you've got a good 15-20 years before you have to renovate that part, and by then, it won't be a huge deal since Star Wars and Toy Story will both be open at HS).