Very short and sweet suggestions:
1. Having the ability to refill your energy/ nerve and Casino Tokens with an extra refill daily at a higher cost (Example: 50 points) because you are a donator/ subscriber. Helps with the points market stability. Hopefully increases donators and subscriptions.
2. Shorten your racing time schedule to 30 minutes over 60 minutes when joining a new race.
Not the best suggestions you will ever read but simple enough to implement.