Whilst I see where you're coming from Goon, I'm firmly in the camp that it wouldn't work with this game. Squad is aimed purely for combat realism and offers a structured multi-role task-force experience. Project Reality had no need for any ranking system, and neither does this.
I agree that Battlefield 2's ranking system was fantastic, and gave all players something to drive towards; trying to get certain ribbons and pins and the weapon unlocks that come as perks to the time and ability to put in. This just isn't something Squad needs - Battlefield was a fun and semi-competitive first person shooter whereas Squad is more simulator. I see your point about how a ranking system could be used to show how adept someone is at the game and therefore would show preference to the people to assume commanding roles on the team. But anyone would be able to get those stats - it's just a time-sink and is only a matter of time before people get to this "position" - it doesn't help at all in the "rank shows competence" model that you would perceive it brings.
As much as I love Project Reality and the real potential Squad has, I think it will ultimately boil down to the same situation of PR; you have communities that know each other well and which members of those communities excel in command-based roles simply by playing with them. I hope the game really kicks off and has a huge player-base, but without the rose-tinted goggles on I can see a lot of people buying into the game, but only those seeking the "purist" experience for combat sticking around - again, the same situation as Project Reality in some regards.
Some good updates coming through Melbo! Looking forward to it hitting Steam and getting my hands on it!