Only one problem... How do you rank someone in a game that requires team-play for 75% of it's game modes?
You couldn't do it based on frags alone, that would just mean Deathmatch players would get the highest ranks.
It's a nice idea but not really implimentable for MoH.
Just to make one point, though.
You said clans are pointless... I beg to differ. You said the next player on a public server is as good as a clan mate. I get on my knees and deplore to differ on that one.
At this moment in time clans won't make much difference as you won't have many competitive matches yet.
Clan-base has already got MoH ladders up, I think. It won't be long before there will be leagues, cups and continental (and hopefully international) competitions all over.
I look forward to this more than any ranking system that would be entirely objective, rather than subjective.
At any rate, using an example to emphasise my point... the CLQ is a long-standing ranking system for most online shooters. It basically gives scores per week based on kills per minute (using the player's best 90 minutes as it's focal point).
It's so exploitable, though. You don't have to cheat, either.
For instance, on Half-Life I used to play and wished for a higher rank. I managed to get 7th in the world official one week simply by playing only on one particular map, using one particular tactic that ensured masses of kills in the shortest amount of time (For those who play HL, that was Snark-Pit and the Tau-Cannon in the pit... remember those days?).
Now at this time I knew very well I wasn't the 7th best player in the world. I had a crappy AMD K6-2 350Mhz and only an ISDN 64k line. I just put in loads and loads on minutes to increase my best 90 minute score.
That was for a game that is
only deathmatch, too. MoH isn't about deathmatch, so you'd have to score by how players work as a team, how they stay alive, how they complete objectives, and far too many more permutations to list here.
I doubt a fair ranking system would be codable.
The best system is to pit players and teams against other players and teams and see who wins the most over a period of time.
That's why, essentially, I disagree with your post