Airsoft = game?
And to be honest I'm not really excited about MM mainly because it is only a multiplayer addon, and I for one don't even like MB multiplayer. If they added an actual RPG feeling to it, I'd like it though.
But since you're already so far in WW3 I think you should stick with this until it's atleast for the most part finished, and then you could perhaps work on WFaS or MM if you like.