The author should be commended for her extreme originality. The entire premise of P&P and the personalities of many of its characters are turned on their heads and we are confronted with many persons we don't know (and some we do).
This book is based on the premise that both fathers, Mr. Darcy and Mr. Bennet were despicable people whose actions and decisions unfairly affect, target and hurt Fitzwilliam and Elizabeth. Wickam is more evil and resentful than usual (with more reason than usual), and Jane is insipid to the point of catatonia. I'm not sure why Jane's personality had to take such a downward turn, but I suspect it has to do with forthcoming books.
The story has twists and turns that I have not come across in other variations, which is a big plus. The story is fast-paced, action-packed, the evil fail, the good prevail, and the happy ending is a given.
But, to me, a big minus is the heavy hand used for defining the primary plot-mover's personalities. First, there is Elizabeth's saintliness. No one can be that good and noble, especially after the traumas she has had to endure. Darcy, too, is a little too perfect. Since Mr. Darcy is dead, there is no possibility of redemption for him, but Mr. Bennet's repentance doesn't ring true to the same extent that his initial (and subsequent) sins stretch credibility a bit.
While I welcome a new author to the P&P variation roster and applaud what, especially for a first effort, is really much better than many authors who have been at it longer, the book missed being really great despite the imaginative story line. There was a need for a little subtlety that would have made actions and reactions more believable; the author needed to tone down the melodrama a tad and fine-tune the personalities to make them a little more credible. A shade of gray here and there would not have been amiss.
But I don't mean to discourage anyone from reading A Father's Sins. It has definite entertainment value, the editing is pretty good, and the additional story lines she has in the works also sound interesting. I, for one, will be looking forward to them.