This is exciting.
I'm sure there will be a million imperfections but, really it's probably best to get it started with simple, intuitive stats that are easily accessible now and get people started. As it goes on, little improvements will start to be obvious and maybe it can evolve.
I remember playing Fantasy Football when it was just points for touchdowns and yards. So many advanced statistics are widely available now because of the interest from fantasy led to the development of tools to satisfy more complicated fantasy leagues.
Maybe a fantasy league would generate enough interest that people would get interested in finding ways to do advanced logs/demo file parsing that could give us better information about how a game went - tracking events by advantages and situations, for example, would be awesome. Finding a way to quantify uber forces or wasted damage or something like that would be extremely cool.