I fully agree that there needs to be two types of play lists. The social and ranked lists have worked, been part of and for the most part kept the more competitive separate from the casual player. Players soon realize that the social variants have less hard core players and play them to either learn the game or because it fits their more casual style of play. I see no problem with the 1 to 50 system for ranked play as long as the deranking issues are handled. The social rank should, in my opinion, reflect the "military" style rank that is used. The global rank could offer a mix of the two, say a 45 - Commander. I also was very fond of the rank per game type in each play list. the overall "ranked" ranking could either be derived from the overall win loss in ranked or the average of your ranked totals.
Quitters and Derankers had always been an issue. The problem is made worse by an automated banning system that is unable to distinguish why people quit or loose connection. The report system has been and would most likely continue to be abused. I like the idea of the the ban for quitting pr the game type, to me it has some merit.
I respect the MLG players a lot. The are typically the top players of the game, some of which play the big tournaments. The MLG play list, rules and ranking should be theirs alone to figure out. I rarely play MLG, I just don't have the skill yo be competitive or support team mates in Reach. I have never been a big fan of the game. In H 3 I was competitive and enjoyed the much harder competition their.
What I don't want to see is a continuation of what is offered in the current game: One ranked play list, credits for rank that is not earned and forged maps being shipped with a new game.