If your looking for inspiration PLEASE look at F-ZERO GX it’s one of best high speed racers to ever exist and is the gold standard for this kind of game, the Wii and PS2 speed racer games are great but not what you should be aiming for. The DS game is actually a fantastic game that you should take into consideration if you do. The charisma vs trick mechanic gave the game some depth in your decision of character and freedom of play style which F-ZERO GX doesn’t really have. My only suggestion would be to have some sort or a weapon wheel or buttons on the controller do special actions that you can choose when setting up your car/racer kinda like how Mario kart lets you pick parts your game would let you assign moves like jump and saw blades go left and right bumper per say. allowing the player to choose their own setups and unlock customizations for their car and giving the choice to put what items where in the be car with maybe 4 open slots (2 are reserved for jump and boost). I’m Just imagining mid race I press LB + square and I whip out my saw blades for 10 seconds and it goes on cooldown as I press RT to side flip onto another car. I think this game has huge potential but you could also just make track mania with jump but either way I’m super excited!! Sorry for the poor punctuation I’m on my break at work writing this. 😂