You 50/50 +/- 1 system work, I can tell. -_-
It's like, Riot expect people to be the exact skill level as their elo. Because everyone, somehow in Riots eyes, does not want to try or try to get better. Nothing is equal Riot, there is, only balance.
This type of system works when you have a small group of people playing League of Legends, this is perfect for diamond and over because they know the game the best, but even there it fails. You have a player base of 100 million now, there won't be any 50/50 +/- 1 games. I would suggest basing teams the way Mobalytics is basing players on aggression, fighting, vision, toughness, teamplay, consistency, and versatility. Base teams on skills and what lacks, so it's balanced that way. If I lag at farming, put me against a person who knows how to farm but lags another aspect, that I'm good at. This will not be everyone, but most players, when they see him or her doing better at that skill they lag, they will think "I need to get better at that."
I do not consider myself a pro, I can't win every game. But there will be many games, where players played really well, won't be able to carry at all. There is a large chance of us getting a team that can't communicate with us, ward, don't know follow up, or a team that just plain out fed the enemy team.
Sometimes we get lucky. However, I hate the fact that we can't depend on our skill, but have to depend on luck. This game is not something you can put a 50/50 system on anymore, that's not how the world works it's not a casino. Everyone is not at the same equal skill stat, they are either worse or better at one or more things to balance out.
I'm not a pro, many of my games were my fault. But because it doesn't matter if I'm skilled, fed, place relevant wards, getting better. It won't matter because it isn't 50/50 and it's about luck.
Players who put too much time into this game to get better, won't be rewarded for their hard work. Please, understand Riot.
Wards. These things and clearing their things is so powerful it's ridiculous. Most Silvers won't use their trinkets let alone upgrade them. Sadly this is still true more often than not in Gold and Plat as well. Simply being able to see them and spam ping the hell out of them to get your allies attention to ambush or take caution not only saves their butts or nets you a kill, but also serves to further their trust in your leadership.