We're a bit late for this one, but can put it off no longer. Surely everyone who's going to read it has finished it by now: my edition is only 168 pages, and I think that's most of the problem.
IMO there's not enough plot for an actual novel, it feels more like a novella. And the supporting characters seem pure tissue paper too - though they should be good solid Heyer staples. There's a callow young man hopelessly in love with our heroine, there's an ingenue, there's a rakish older uncle, and a wicked older woman. But honestly I can't remember them at all.
OTOH the stuff in Paris with the poetry and the clothes is a lot of fun - I love Heyer's more dandyish heroes, starting with Avon, and her very camp groups of young male friends acting flamboyantly (personal faves are Sherry's friends in Friday's Child).
And rather against my better judgement I like Cleone, even though her infantilisation and lack of agency is a terrible feminist fail. I find her awareness that she's done something silly whilst remaining resolute in her belief that Philip did need to be taught a lesson quite attractive somehow.
So what do you reckon? Is Cleone infuriating or oppressed? Is Philip's Parisian sojourn the best thing about the book?
And which edition do you have? Mine finishes "Oh Cleone - I shall write a sonnet to your wonderful eyes!", which implies that he will retain much of his town gloss, but I think that other editions have them returning to the countryside which seems a shame to me.