If we're looking ahead as to the future of that area, here's what i'd do.
Firstly, we're presuming that indeed, River Rapids isn't coming back. For all intents and purposes then, there's nothing beyond Buzzsaw really holding the area to a theme, and i'd imagine Buzzsaw would be rethemed out of respect at some point anyway.
What i've thought Movie World & Sea World have always done really well is putting on big crowd pulling shows. Stunt Driver, Main Street Parade, the Jet Ski Show, the Dolphin Stadium etc. etc. etc. and yet to this day there's still not a unified large auditorium/stadium/space for people to go to see unique shows beyond the stage in front of the globe. This has meant entertainment has ended up in weird spots like out of the front of the ice-cream parlour or just sporatically in the most of random of places, which has drawed at best, a passing crowd, and not the thousands Village pull in their respective stages & environment.
With this in mind, i'd go back to basics and redevelop Gold Rush into old school Dreamworld Village Green, and here's how:
Redevelop the cinema into a soarin' attraction and build into the Eureka space.
Open up the pathway to allow for a parade to run all the way from the fountain right up to the Dreamworld Auditorium
Redevelop the Dreamworld Auditorium, modernise it onto a much more useable daily space, rename it in memory of the four that tragically lost their lives, and create a gorgeous entrance space with four, tall, distinct palm trees at the entrance roughly where the Hollywood House is now.
Re-theme Buzzsaw to the Thunderbolt, essentially repaint the ride to look like one of Thunderbolt's signature loops
Re-develop the horrid pathway systems that the Sandersons Group put in when they built The Giant Drop and create a more accessible, open & green thoroughfare through that entire corridor of the park.
Add more Main Street style facades in and around the Soarin' Style attraction and create new retail experiences and spaces for people to enjoy
I've always thought @Gazza was right on the money with some kind of Gerstlauer Eurofighter into that space, and I think given the tremendous value you get from them (just look at Abyss) not to mention how great they are in a tight space, this would be more then ideal. Combine that with a Star Flyer and you'd have a revitalised area that would honour the past, be a worthy response to what Movie World's doing next year (if done right), would be able to manage the capacity lost from River Rapids and offer guests new retail and show experiences that can be refreshed often. And to top this all off, this would then open up a clear and open path to expanding out into where Blue Lagoon was, and also give Dreamworld a clear and appropriate corridor to expand into should they build a second gate in the future to link to the Coomera Town Centre.
Thoughts?
I'm going to mood board you guys while i'm here.
Above - Buzzsaw paint job inspiration
Above - Look and feel for the new buildings that would wrap around the other three sides of the Soarin' theatre.
Above - Blue Lagoon could be redeveloped to look like this in the future.
Above - Inspiration for some of the gardens and pathways that could interconnect the area between Rocky Hollow, Giant Drop and Village Oval.
Above - super rough idea of what the entrance could look like for the Dreamworld Auditorium.