My suggestion to you OP: before coming to the community with your idea, perhaps you could figure out more of the details and try to think of the negative effects that your suggestion may come with. It's important to not be biased with your own suggestion because the best ideas have downsides. It's all about figuring out how to improve your suggestion to get rid of the cons. This would be like me going to the US patent and saying that a perpetual motion machine, and expecting someone else to figure out how to make it work while taking the credit for the idea. Personally, I think tournaments for all game modes would be uber fun, but without the schematics on how to make it work, it's just not going to happen. I hope you take the time to work on your idea and perfect it so that one day it could be a reality.
Best of luck to you :)