I'm pulling back in time just a bit. My favorite has probably been Rising Son
. I love Jake in this novel, as well as the entire crew of the Even Odds
. I would love to see them again.
Least favorites were the DS9 volumes that dealt with the Mirror Universe. I have never liked that story thread, not since all the episodes after "Crossover." I've never met the story yet that has redeemed that whole universe for me.
I haven't actively disliked anything since then. There are some strong "meh" candidates in there, but no real dislike.