Ah! I read A Countess Below Stairs a few years back. I remember having some issues with the secondary characters (as in, I thought there were too many of them, and too much time spent on them instead of, yanno, the MAIN characters and story), and I don't think I was entirely sold on the heroine's feelings for the hero, but it was enjoyable enough and different enough (WWI-era, yesss) that it has stuck in my head, nonetheless. I've actually been considering giving it a reread, so it'll be neat to hear your thoughts on it.