Nothing's perfect in this world. I mean, don't get me wrong, I also find some of your points to be good, but I don't think it would help much in most cases.
1-1A) It's a great idea but, in a contradiction, it would also be boring as well. If this happened, you wouldn't have much challenge and you won't really know how much you improved the game if you are playing with the same caliber as yours. I mean, you won't really grow unless you've have had challenge.
2) Everyone deserves the right to play. I mean, you purchased a console and also pay for your connection, so no matter what your skill ranking is, you would still have the right to play online and also, that's matchmaking. There are also several factors affecting them other than what you mentioned.
2A) Read out this link: Activision Support
2B) Wouldn't really be fair for those players who are also trying out their best to stay in matches. If you're sole intention is to rage quit everytime you are losing games, doesn't see really give out much point for the game.
3) Haven't heard of that but, would also be a great idea if that would happen.