The next 'main' storyline books will be Sword of the Jedi next year, which I'm looking forward to because I've always liked those characters a bit more than the originals. Crucible wasn't bad but it felt...unnecessary? Like a filler book.
Not sure what you mean there...she's a Sith, and she has a few moments of self-realization at the end of the last series where she knows that trying to follow the Light Side is beyond her capacity and just runs the other way with it. It's not as dramatic as her attempts to be a Jedi, but it feels realistic at least (not everyone is cut out for it; redemption is a rare and special thing).
I've general found Denning's stuff to be decent...certainly better than some (looking at you, Traviss) although my personal favorite would go to Matthew Stover (Traitor and the Ep.III novelization).