Personally, showing more context in the FTS box would be a bit useless since it only shows the first hit in a book and more than enough context for the hit in the right hand box.
My preference is to use FTS to locate books and then use the e-book viewer to open and search within the book.
Since FTS will take multiple search items with various options, perhaps a bit of work on creating searches would be a useful application of your time. See
SQLite FTS5 Extension on the SQLite site for more information.
See attached images.