Just finished Deep Black by Miles Cameron. It's the second and final in his Arcana Imperii series.
It's military sci-fi space opera that does a lot of things right. The main character isn't an unlikable bastard, she grows and changes throughout the series, it's not super hard science but it's also not hand-wavy fantasy, they deal with acceleration and relativistic effects, etc. . But it also bothered me - she's a bit of a Mary Sue (although this gets addressed); there are huge swathes of actions described that probably weren't necessary like pilots going through all of the check steps, launching, doing actions, landing; some of the antagonists were a bit mustache-twirly evil. Overall though, it's still got me thinking about it and turning it over in my mind, so I'd still recommend it.