My suggestion is based on being able to have greater competitiveness in the leagues by eliminating the rookie, pro and elite difficulty levels.
I used to play an old soccer browser game where the leagues were divided into divisions. The first division is the highest league to compete in, suppose there are 16 players in each league, at the end of the championship the last 4 are relegated to the second division. Suppose there are 2 second divisions, the first 2 players of each go up to the first division and the last 4 of each go down to the third divisions, so there will be 4 third divisions and so on ...
You can also think of implementing this system only for players level 20 who wanna join the competitive system while maintaining the current system for the others, so those who want to have a style of play more similar to an e-sport are satisfied, as well as those who play more casual.
Obviously, in the new system, a fixed time and days should be set for all, as well as a single duration of the race. There are many details to manage and set properly but i think is a good way to bring competitiveness to the most experienced players of the game