If we're really being nitpicky about how many female Carpathians have been featured as leads, there have been more than two: Francesca, Desari, Syndil (not necessarily a lead, but she had her own story) and Savannah. I don't think Destiny really counts, since she was born human and was converted.
I had mixed feelings about this book. I would of course recommend it to anyone who's a fan of the series already, because while Feehan does tend to go off on her "cause" tangents, Dark Destiny still works well as part of the series and furthers the storyline of the Carpathians in general. I'm not sure anyone reading this as their first "Dark" book would be all that impressed though, and that would be a shame since there are some really wonderful books in the series, books that are better than this one.