Yes, I did. Straken is a great read and very reasonably-priced, and I'm not biased at all!
I gather that animations about the space marines and an inquisitor are currently being made: GW has branched out considerably in the last few years.
It seems to me that one of the big problems is that people will want to see space marines, probably fighting chaos space marines, but a lot of their background is either slightly ridiculous in practice (spitting acid!) or doesn't make for good drama (feeling no actual fear, and having very little in the way of personality). Even getting them into the same shot with characters who are less than 7 feet tall would be difficult. (I always wondered what the marines did when fighting people in normal-sized buildings.)
I think you would have to bring Chaos into it: that medieval aspect is really what makes 40k different from a more miserable version of Star Wars or Dune. It could be good, but I think that would involve making it very strange to preserve its uniqueness, rather just being super-soldiers shooting monsters, and that strangeness might well drive people away.