WELCOME!!!
First... the good news... we are working hard to make the Space Marines a reality at a skirmish level!
This has not been done successfully, because of how awesome (powerful) the Astartes are, but we are working carefully to do the justice. Trust me when I'm saying that we are paying EXTRA attention to details to capture their flavor, fluff and 40k playability, while still making them fair & fun at this scale. We have several Space Marine NUTS who have more obscure knowledge on the subject that the Black Library.
When the times come, we would be SUPER honored to make sure our work passes your ever vigilant eyes.
You (the Space Marine fanatic) is our 'target'... if people like you approve of the final results, we will be very pleased.
The not-so good news... the work will take some time. There are lots of little details on game mechanics that are being polished (under the hood of the game) so the Space Marines are fair. We are working on the 2nd revision of the Chaos Cultists, which are led by a Traitor Marine. This 'closed' test have allowed us to tweak the game mechanics for the next step.... the Space Marine Scout Squad. With the SMSS we will introduce the Astartes, and tweak them properly. That will lead to the Space Marine Chapter Squad, which would probably be a 5 man Combat Squad (equivalent from 40k). Rather than rushing things in, we are taking time to do things right.
The even GREATER news... we would love to read your stories! Go ahead an post whatever you feel like sharing on the 40k section.
PS: Go ahead and start playing Death Squads... I know the SM are not available yet, but you will get a sense of the game, wetting your appetite for the Astartes.