At the risk of typing into the void, I gotta say that I enjoyed the Varley novel. Nerds often describe M John Harrison's The Centauri Device as the novel that deconstructed space opera, though I don't think it was entirely successful. In any case, Varley's The Ophiuchi Hotline has that same deconstructive vibe vis-a-vis first contact-style stories and, I think, it more squarely hits its targets.
Much to my shame, I've picked up a well-recommended Warhammer 40k novel. I'm not really into military sci-fi as a genre, but I appreciate the (sometimes overwrought) efforts at worldbuilding and machismo.
It is with a deep and abiding shame that I say that I mostly enjoyed the first Warhammer 40k novel that I read. Granted, it's my understanding that it's one of the most highly recommended Warhammer novels. In sum: military sci-fi that valorizes the martial virtues; self-conscious pretenses to granting war the grandeur and dignity of Homeric epic, though this comes at the expense of three-dimensional characters as well as the political and social intrigue that should accompany a galaxy-spanning war machine. I think it would be worthwhile to think about these novels as modern-day pulps.
I am reading a second Warhammer novel by a different author--it is also different type of story set in a different time period--that I'm enjoying much less.