In a perfect world, I'd level the whole thing and start fresh.
This isn't a perfect world, so I'd overhaul the ride to better fit the 1930's atmosphere of Sunset Boulevard. A gangster theme, perhaps? Maybe a jazz theme?
If we keep the rock & roll theme, we should do what Star Tours did and have a large selection of songs from different bands (including Aerosmith) and have a system randomly select a few for a particular ride.
If we want to fit in with Sunset Boulevard, we should ditch the rock & roll theme all together and make RRC a Rocketeer-themed coaster.