Separate Rankings For Different Game Types

I don't know how difficult this would be to implement, but how about different rankings for different game types?

This idea came up as I have played a few capital games recently with a player ranked staff sergeant who seemed to have no idea how to play this type of game. They are obviously a skilled player, just not at capitals.

Just thought it would be helpful to see if a player is good at a particular type of game, rather than expecting a high-ranked player to know the basics of capitals.

I would love to have separate rankings per game mode, but this would require quite some change in the existing systems. Also I think the actual rank should still depend on the overall score, as some people just play one or the other and I think both ways should allow you to progress in the more general ranking.

I dont want seperate ranks, as ranks just tell you how good you are overall.
What I would like is a statistics page for a member, where you can see approximately how good he is in increasing capitals, how good in increasing DM's, how his FOG skills are, how he does in domination, and how he does in fixed/capped/no card games.

However, I do not have any real clear ideas about this, so input could help

I was talking about different rankings, not ranks. Basically additional "player ranks" pages that only count certain aspects.