This is only a small idea, but I've been thinking about how the backstory for the Phantom Manor is so under-presented in the parks. This could make the queue a bit more interesting, as well, with very low cost.
They could place signs chronologically along the queue that explain the backstory. The top-half would be in French and the bottom-half would be in English.
A man once called Henry Ravenswood (born 1795) struck gold here in Big Thunder Mesa and founded the Thunder Mesa Mining Company...
...He used his gold to build this very house with his wife Martha and raised their daughter, Melanie Ravenswood (born 1842)...
...After many years, Ravenswood's luck soon ran out when there was no more gold left, and the mining company dug deep tunnels under the mountain...
...Meanwhile, Melody had fallen in love with a young man at the mine, who soon asked her to marry him. However, her father did not approve...
...Mr Ravenswood did everything in his power to stop the wedding. Perhaps that was a mistake, because they say you should be careful what you wish for...
...A horrific earthquake struck Thunder Mesa on the day of the wedding, killing Henry Ravenswood and his wife. The groom had disappeared, and Melanie was never seen again...
...Some say she stayed in the house on her own, wandering the halls and waiting for her love to return. No one knows, however, because each night, strange laughter could be heard inside the house, so men have been too afraid to to enter... until today...The signs would probably used a more spookier tone than I've used, but it would basically be something like that.

Hopefully, guests would look forward to seeing each sign, so they won't get bored in the queue.
This might not be such a good idea, though, because it was the Imagineers' intentions to let guests speculate what the backstory is. Plus, the actual backstory has never really been revealed.