I would love for this to happen. If there is no word on competitive changes in 2.2 to nurture the longevity of this system, then we'll entertain ourselves.

If we want to replicate competitive, rated play with no rating system there would have to be a record of win/loss or points distributed. Rank and recognition are good ways to inspire people to participate. Problem is it would require a somewhat large number of groups to not feel stale. 3-4 of the same groups going at it each week and people will lose interest quickly.

Gear disparity is another problem. The difference between an i70 and i90 player is noticeable in damage and survivability - teams with less gear would be at a disadvantage. There simply aren't enough rank 30s to form the coordinated groups for this system to work effortlessly.

Rank 20+ is my proposed foundation, as I feel all essential skills and traits should be covered at around rank ~21 (at least for Paladin), but the gear discrepency is still there.