@Riot Make a queue for people with new accounts (I.e "Boot Camp")
We need something that can be balanced for newer players, while you've made a lot of progress for making starting the game easier, the smurfs are reversing all the work you did. A true blue new player is not going to be able to square off against a silver, or a bronze. Irregardless of whether or not if they have runes or not.
In short we need a boot camp game mode, similar to the boot camp game modes of Call of Duty. We need to force levels 1-20 to play bots with increased IP gains. The only reason older players, when they make a new account, play normals is because the ip gains in the Co-op vs AI are totally laughable, sure you will get the bottom of the barrel people who will still trash talk just for the reason of trash talking, but this way people can really learn different things about the game, especially if they can buy the champions they want until they really hit the grinder at level 20. Let me put it this way, the only reason people START to play this game are one of two things, they got goaded into it because a friend said a champion would appeal to them, Or its just because of the world creation (Magic, steampunk, undead etc). You have a really good thing going here, its just we need to make people stick to the game. I can't count the number of friends I've tried to get in just to lose them because of smurfs or just the impossibility of getting that 6300 champion.
Also you could make explaining runes a lot easier at level 20. The game after they hit 20 just have an event pop up explaining they've unlocked the top tier runes, and because they have all the IP from the "Boot Camp" they can at least make one page of runes, while still having the actual game mechanic explained to them, and since they're playing in this co-op mode they can't get immediately stomped by the more coordinated players. Everyone wins except bottom feeders who need to stomp level 10 accounts to feel good about themselves.