This is actually a set of three novellas with a common setting and the same set of characters (although each novella has its own h/h). I enjoyed Julia Quinn's section the most - 4 stars. Her characterization of the painfully shy Gwendolyn is very well done and the love story is believable. Connie Brockway's section felt disjointed and choppy even though both h/h are potentially wonderful characters - 2 stars. Eloisa James' section was not bad, although it doesn't make sense to me that Hugh (the hero) would go from completely clueless about his supposedly long-standing love for Georgina to completely besotted and committed to her in the space of a few encounters at the house party - 3 stars.
Not sure about the epilogue - looks like it was written by Eloisa James - it is totally silly and adds nothing to the book.
Maybe this is an unfair comparison, but Mary Balogh's "A Matter of Class", which came out about a year ago, is an extremely fine example of what can be achieved with the novella format for a historical romance. The stories in "Lady Most Likely" don't come close, unfortunately.