About the restriction for mods, like I said, ideally community feedback would be listened to and a consensus could be reached over the mods that we all feel are good enough to deserve ranking.

About your other point, the whole point of a ranking system is to encourage competitive, tryhard play. If you are casual you wouldn't care about your rank anyway right?

You also brought up something about players not getting to learn from the pros. Well, don't forget these ranked rooms won't remove user rooms from the game, you'll probably run into higher ranked players all the time in tourneys if nowhere else.
Also, the system allows you to always be playing with people who are better than you, because if you are ever superior to your current 'tier', you will rise out of it!

Also,

'Hey this is just like the ranking in League'
'Hey this is just like the ranking in Starcraft'
'Hey this is just like the ranking in...'

I feel like this is a sign that this kind of system works in practice too.