Generating library override operation for a production character (like Autumn in Spring) implies going over and comparing several hundreds of thousands of RNA properties... No way to make this lightning fast, some ideas would be to try to remove (prune) paths that are not supposed to change ever... Not yet sure how to do this though, we already skip a good share of the whole RNA tree.
{rB2a38b857f7dc33} already tackled all low hanging fruits here, any further improvement will likely require deeper work for much less gain…