I agree with the premise here but the amount in Champion is too high. Getting to champion is an incredible achievement and requires tons of investment so they deserve to be paid out well but champion is just not something that many people will ever be able to do no matter what. Giving the few people who can afford to that big of a slice of the pie is not really in line with aggroed's the smallest fish to the biggest whale idea.

Because of player distribution, champion doesn't have to have the highest percentage of the pool for the players in champion to make way more than anyone else in the game. I think if anything, we should be encouraging players toward something aspirational but achievable like Gold. We can call gold the middle class and give the bulk of the rewards to them as a whole, while still rewarding higher league players better individually.

Maybe something closer to:
Bronze 15%
Silver 20%
Gold 27%
Diamond 18%
Champion 20%

I don't have access to all the numbers to know what this would look like in practice but I'm guessing if it were broken up like this you'd still have progressively more going individually to people in higher leagues.

Does anyone have the stats of games played per league?

PS: if we're going to be voting on this stuff, we should have access to relevant stats