I put No simply because I don't think the premise really works. How can you really Role Play your commanders all hanging around, the whole 40K system is build purely for combat and without that combat built in the commanders have little to do. Sure you could plot with other commanders, but I just can't see an Ork, an Ethereal, a Demon, an Inquisitor and a C'tan sitting around deciding their differences over <insert generic 40K beverage here>.
If you want to run a game ask for people to play several like minded or sided characters. The premise of almost all RP games is that the players have something in common or a system to oppose each other. On a forum you need someone to moderate it or it falls apart far too quickly.