It's a big call, but I'm going with Trisha Ashley's The Urge to Jump as my favourite author heroine story. Usually I hate present tense, but in this book it works. It suits the opinionated heroine and the quirkiness. In fact, it's the book that hooked me on Trisha Ashley's warm English women's fiction/love stories. Now her A Winter's Tale is a Christmas re-read for me.
And yes, I am already thinking about Christmas reading -- I tend to hoard good books to read then while eating Christmas cake and drinking milk :)