It seems like of all the primarchs we've gotten to know thus far, Corax had stayed the closest to his roots. That really makes him stand out -- he's not just the leader of a space marine legion, he still belongs, heart and soul, to Deliverance. Hell of a guy.
I dunno about Guilliman, he seems kind of detached in that utlra-intellectual kind of way. Alternative interpretation: Corax acts more like everyone's brother, where Guilliman is everyone's somewhat-distant dad.
Can't say on Sanguinius, since I haven't read Fear to Tread yet, but I suppose he's an okay guy. :V
After I finished Deliverance Lost it ocurred to me that Corvus and Nasturi are probably the closest we'll get to a canon love story for a primarch. And if you read between the lines it's a pretty good one - Corax even says (though not in so many words, of course) that he trusts Ephrenia as much or more than he does his own captains.
I like the specks of light you put around Corvus' head, and the lines around the exterior of the pod. It reminds me of the flashback scenes early on in DL where we get the glimpses into Corax's mind and see how hyperintelligent he is, a master of physics, engineering, and a dozen other fields even at birth. Somehow the detail on the picture calls to mind the idea that even at rest Corvus' mind understands, dissects, and contemplates such things as the pod's structure, the makeup of the cavern walls, and even despite being so far underground touches on the stars above.
Combine that with the touch of him sitting in the light (symbolic of greatness, destiny, wisdom), and removed from Nasturi and her lantern, which could easily be a stand-in for humanity and such concepts as warmth, compassion and love, and as a result you have a piece that's very evocative and moody, well-suited to Corax's character. I think you hit this clear out of the park.
Thank you very much for such nice comment! I'm still in progress of reading the novel. Just want to expand a pleasure. The idea of the sketch woth Corax and Nasturi came at once after I read about their first meeting. "He took her to his ship, wow!" That was quite unusual thing for such being as a primarch. But I think Corax is more human than most of his brothers. And he's similar to Alpharius in this option.
You managed to describe my thoughts about those sketches. ))