Well, I've decided to pick up David Mack's VANGUARD series after reading watching the latest season of STAR TREK: DISCOVERY. I really liked his fusion of both the Original Series era with the 2017 CBS series, having only a few seams showing in the resulting stitching up of the two franchise sections. So, I was intrigued by the possibilities of a series seemingly based on combining the premise of DS9 (a long-range space station on the frontier of Federation Space) with the time period of the Original Series. So, how did it work? Remarkably well, actually, and Discovery could take a number of lessons from David Mack on how to write "dark" Trek.
For anyone who knows me, I am a fan of Expanded Universes. There's only so much you can fit into even long-running series like Star Wars and Star Trek. Indeed, these are my two favorite franchises and I have devoured hundreds of books set in them. Some people have dismissive attitudes to these books but they're missing some real quality works. The Thrawn Trilogy, Rogue Squadron, Star Trek: Vanguard, Star Trek: Destiny, The Department of Temporal Investigations, and more. If I had to praise my favorite Star Trek series, though, it would be New Frontier. Essentially, a novel-only series combining original series wackiness with TNG stuffiness to great action-adventure and humorous effect.