The Problem with new Champs on PBE

Everytime a new champ is released on PBE you have the problem that everyone wants to play him and you get many leavers in Champ Selection. And way too often there are people picking that fast that you have no chance to test the new Champ. Especially because when the Champ is released, custom games are limited to 2 or even 3 players. In my case like non of my friends has an PBE acc so i cant even test the new Champ in a Bot Game. So in my opinion the PBE needs the One for All game mode always available for the latest champ only. Of course that is much more work but this could be a fair solution for everyone to test a new champ on PBE when hes released. Because people with slow pc's have almost no chance at all to get the new champ except for the case noone in the team wants to play him but thats unlikely..