My only frustration was that you had to essentially master the game completely to unlock all the racers. Sure, rewards for mastery all the way to the highest levels of the single player mode are good, but I felt they should have changed it up so you unlock all the racers earlier and offered some different rewatds for the end. Or maybe I’m just salty that I had to go to the very end on the highest difficulty to play as characters I wanted to play from the start, in a Sega racer, no less, which are generally harder than most. At least in a game like Smash Bros Brawl, you just had to beat the final boss to unlock Sonic, you didn’t have to perfect it on the highest difficulty.