FistofLife: I actually read your post carefully enough. If you can't see drawbacks in your suggestion, you probably have to start reading others' posts and react adequately to them.
I thought you were a smart guy Sir, is it really that hard to understand how you cannot noob farm using this?
I guess you don't make any difference between "farming" and "playing against whitebelts with an alt".
When you let ranking system work in private rooms, you get people locking it (+ supposedly ghosting it) and farming ELO. No matter what belt they have, white belt or god belt. This can only be prevented by disabling ranks in such rooms and keeping them for official only.
If you want to prevent people with huge qi difference from getting ranking points for playing against each other, I don't see any reasons for implementing a whole new system instead of tweaking the current one. Keep it only for qi-based rooms, add 'rank groups' to prevent brownbelts who play a lot from beating 10th dans and that's all.
As for mod rotation, why not to have more official rooms? There aren't THAT many mods people play on regular basis and there are even less mods that can be considered 'fair'. If players care about ranks, rooms will be crowded enough not to stay empty all the time.
Also please stop adding "esport" to every idea that includes rank / game client upgrades.