Every time there is a new champ, there's a massive increase in dodges, because people want to play that champ and nothing else. I propose the following solution:
Increase the dodge penalty timer. I'd personally make it an hour.
Make the timer apply both to the PBE account and the live account it is linked to.
Ban the player from PBE after a certain amount of dodges in a week.
Edit: It should also be stricter on leavers. ~30% of my games over the last few days have had at least one afk, quite a few with 2, and one with 3 afk on one team.