You know, Deathworld is one of my favorite 40K novels, but I never really think of Lyons as a favorite author of mine. Maybe just because he's not as prolific as others? I dunno. In any case, I liked DMW just as much as Deathworld.
This novel is essentially a riff on the tale of how war affects everyone, almost a War & Peace sort of vibe here, except during a necron ... is invasion the right word? I mean, they get dug up & they retake the planet. So ... reclamation? Oh, also, this novel is ostensibly a Death Korps of Krieg novel, though Lyons obviously very early in the planning stages realized that the DKK works MUCH better as background characters, just being creepy as all hell during most scenes. The few scenes where DKK members speak/interact, it's almost more unnerving than them just staying silent.
Our three protagonists are Gunthar, and I can't even remember what he was originally, but I see him as kind of middle management: his position in the world isn't GREAT, but he's got a hab unit, he's doing OK for himself. He's secretly dating Arex, who's the governor's daughter. She's out of his league, but they love each other, and he's not like the guys her uncle tries to set her up with.
Her uncle Hanrik is also a fairly main character, as is Commissar Costellin, who's leading a regiment or whatever of the DKK. He doesn't really fit in with them, and often has clashes with Colonel ... 182? 186? They go by numbers. But he's determined to be a good commissar for them.
Lyons approaches this story in an intriguing way. He deals more with the human fallout & the emotional impact of the battles, rather than showcasing the battles themselves. He goes into the thick of it for a couple of important battles, but this is mostly about the emotional arc of each of the characters. Since it's 40K, obviously you've got to adjust expectations fairly quickly.
I really enjoyed this book & hope Lyons did more in the world.