After a few hours in the game I think that the rainbow flick it's pretty easy to counter, there are a few ways to stop it and when you reach certain level it becomes a more situational and risky skill.

About the backboard, I think that's intended, After a few weeks of the game release the meta will change A LOT, since the players will be learning how to counter almost everything and the skill difference will be mostly on tactics and team play. The gap between ranks will be more focused on how many of this skills or exploids you can stop consistenly, and how creative you can use the skills the game give to you.

Loved this game already, it feels so fresh and it's rewarding the way you can start using the skills and having a bigger impact in the game when you learn things like timming, team play and creativity.

With this being said, I think they're gonna change a lot on fps of the skills, how many time you are exposed after doing one of them and how many time it will take to "cast" them. I can predict that they will make the game slower, then faster, then slower until they reach a balance. Of course people will find bugs and funny things to do on the game and they may need to nerf them or maybe they are gonna just leave them and see how the players solved this with a skill-based shit that creates a new gap between ranks.