Could it be that I could like the Wallflowers more than the Hathaways? I was introduced to Kleypas with her Friday Harbor series by my sister, the romanceaholic, and enjoyed her writing so much that I ventured to the Hathaway series. I thought "surely, this is her best writing". The verdict is still out, because I enjoyed Secrets of a Summer Night immensely.
Kleypas has a real knack at writing characters that you want to read about, even if you really can't put your finger on why. Annabelle could have been classified as snobbish at times, yet you don't hold it against her. Simon, downright rude and maybe *gasp* not even remotely suave, but you still love him. So what gives? Playful dialogue and the developement of good lesser characters I believe. I laughed heartily at many 'wallflower' moments, most noteably at the audacious rounders game.
A great read all and all.