Just a few random predictions (perhaps I come back and read this in 50 years, who knows

)
-AT would have switched ownerships a couple of times
-RMT/KC replaced to some extent
-Duel getting removed and replaced by something else
-Mutiny bay buildings getting redone
-Increased hotel capacity
-Another two B&M coasters (or more)
-Another several coasters
-A LOT more, 50 years is a long time in terms of developments ye know
It could even just be abandoned/sold off if numbers dwindle too much over that period, a bit like what happened to Camelot