Good Idea for ranked

I have this great Idea on my mind of improving ranked which I will talk about is

Champion restriction

What it is that in order to play ranked you must at least play a (x) amount of games in normals (all mode) in order to play ranked.

Why would it be a great Idea? Because today, I encountered a Nidalee (enemy) who was a first timer (using lolnexus) was first timing with a skin she bought with a champion and what she did was ruining a game because she had no idea with Nidalee's ability and builds (she was doing baby damage probably less than 200) Now I just lost a ranked game because of my Vayne (another first timer) who had no idea how to play Vayne, csing horribly, she didn't knew that E (Vayne's ability) on a person would stun until I told her, etc... Iv'e encountered many first timer back then, then I got fed up how they have no knowledge and feeds the whole game.

I don't really care if you guys are telling me to get better because I highly main supports and I was struggling a lot when I played... It ruins the fun for people who might have first timer on their team in ranked and they know how I feel. It might improve ranked, but tighten restriction too much might cause problems for e.x: play (30) games to play as [Champion Name] in Ranked <----- people might end up giving up on playing it. I would suggest like at least 5-10 games which is short (depends on people's skills)

I hope you guys like my Idea.

If you disagree with the Idea, then give out your idea or opinion.