More in the same price range than cheaper, I enjoyed (quite a few years ago, so I can't vouch for the current quality) Chez Françoise in the Aérogare des Invalides in the 7ème. They do still exist and their menu is posted on line. They are open on the weekend, and reviews are mixed but all in all what you would expect at this level. It is popular with parlementarians as it is close to the Assemblée Nationale. Its location is a bit hidden from plain view so it does not get many tourists.

Although you started this thread for personal reasons, it has the potential to be a valuable service for all Flyertalkers - thanks for starting it!