I would suggest special events, when iGP announces they will put on a limited time special event to all managers, such as like everything is 50% off. Here's my event suggestions:
Double Tokens from Sponsors! If the event happens, sponsors will give out double tokens after a race has finished, for example, iRacing normally gives out 3, and with the event, 6.
Double Earnings! If the event happens, sponsors will give out double the money!
Third Sponsor! If the event happens, for a very limited time, you are able to sign a third sponsor for half the earnings given by the second sponsor.
Christmas Event: If it's Christmas, for only one day, the tracks will all have snow, and you have to find the secret Christmas car (in 3D, touch it) to get 5 Tokens!
Double Reputation: If the event happens, you will earn double reputation if you gained reputation after the race! If you lost reputation, you won't have double of reputation gains.
Halloween Event: If it's Halloween, tracks will have scarecrows, ghosts, and find 5 pumpkins in 3D (touch them) to get 5 Tokens.
Sale Event: If the event happens, everything "buy" related (rushing HQ upgrades, shops, car equipment, etc.) will get 50% off!
More suggestions? Comment them down below. Anniversary events should have very special ones. It's up to your own to say what more.
Error: The "event" in the voting description should be "events".