Robert

It's horrible isn't it? You've got ideas running around but then when it comes to writing them down they just up and leave. Or atleast for me anyway

I love Dr. Who!  Just putting that out there.....
          

If you aspire to be great then make it your own story not something that was for the most part outta the old black templars codex.make it have more feeling, yes everyone loves the space marines but you need go humanize them somewhat to make them relate able to the reader. Just some constructive criticism for you.