GT6 had to give you big payouts because the normal economy was so stingy. They were a bandaid to a problem that shouldn't have existed in the first place. I'd rather instead of that sort of patchwork system they just figured out how to fairly reward the player for the time spent racing, and balance the prices of cars such that a reasonable investment of time allows the player to buy the car that they want.
I would suggest that for the most expensive ultra desirable flagship cars, the player should be able to afford to buy them with the earnings from between 2 and 5 hours of gameplay. That makes them hard enough to afford to give a sense of reward when you do finally get to buy them, without making them unobtainable to those who are time poor. 20-40 hours to afford one car is unreasonable - even MMOs aren't that stingy with gear.
The joy of the game is driving cars, it should be encouraging players to drive as many cars as possible and only holding them back just as much as is necessary to retain the pleasure of acquisition and ownership.
While we're at it, daily bonuses can bugger off as well. Make me want to play your game daily by making a good game, not by creating fear that I'm going to have to grind extra later on if I don't keep my bonus high. That's gacha game bollocks, and has no place in a Gran Turismo game.
