Playing champions in ranked should be tied to mastery
Now hear me out before you spam downvote, the ability to play a champion in ranked should be tied to champion mastery.
How many times has a brand new champion come out only for that champion to flood ranked and 8 out of 10 times feed and ruin your game?
How many times do you get that "first time X" guy who does terribly even if he gets a ton of help from the jungler, just because he doesn't know how to play the champion?
I think that, in order to play a champion in ranked, you should at least need that champion to mastery 4, maybe even 5, That way you will at least have a decent idea how to play that champion, a decent understanding of the mechanics, and a pretty good idea how to build them.