We need an overlay for premades and ranks

In champ select as well as in game. Champ select would be your team only for the premade overlay though, so as to keep out unfair disadvantages of knowing/informed guessing of who is going where (for an example, if there is a duo on the enemy team, it is a good chance they will be the bot lane, and if they chose something which normally is a flex, like a Trundle, Lux, Morgana, or Brand, where that team has intend for them to be the support, it could be seen as defiantly the support and not any other role by your team, removing the flex of that pick).

In game both should be visible for both teams. Knowing who is premade and their ranks are very important. It allows you to predict if you should play passively expecting a camp, because the jungle is premade with your lane, or play aggressive because you are facing the 1 solo player on a team with a 4 man. Also, it shows you if you are that unlucky player who is facing someone way out of your league, like a silver 4 facing a platinum 5 (yes this does happen because those players usually are drafted as MMR counter balances to skew the team's MM average closer to their opponents).