Premade Limiter

Real talk Riot, from what I can tell of the people D+, they tend to have multiple accounts.

I'm not entirely sure how this new limiter you're putting into place does anything to solve your arguable primary issue of immense smurfing in the highest tiers.

I think a more fundamental solution would be to encourage a system which links accounts together, or some other synchronization toward that end. OR provide more meaningful rewards for the highest ranks of challenger. Think special skins, etc.

What's more, you already have a lot of issues with matchmaking, does limiting grouping possibilities result in overall improvements to that end? Is it now only possible for people in those tiers to face people within the same constraints as you've imposed? If not, doesn't that seem odd?

Of course, I'd love to see you develop a far more intelligent algorithm toward assessing skill than just w/l, as this would go a long way to proper matchmaking (especially in this area of Boosting which we're so fond of discussing).