It's unfortunate that so many of these books are harder to find now (even ones from only 4 or 5 years ago are hard to find!). I've been trying to find a few of the Voyager ones for years
I love the Psi Corps, and Bester was a fantastic character.
I really liked Peter David's early works, like Imzadi and Q-in-Law, but Before Dishonor ruined his image a bit for me. Although he can write Q extremely well, I will say that.