TBH the only way a Karts game won’t have any similarities to Mario Kart, would be to take a more realistic approach and make it like real kart racing or as close to real kart racing without making it too racing sim-ish. No matter what they do, I’m sure it will be fun.
In the end, the discussion will come down to the use of rubberbanding. And as much as I hate the concept (good players shouldn’t be punished, bad players shouldn’t be rewarded), I understand it serves a big role in keeping the game fun.
I honestly hope Pickletail will come up with a unique way to make the game fun, WITHOUT the use of rubberbanding. Maybe split the race into a series of mini-races? Or perhaps allow losing players to skip portions of the stage but at a cost? Make the entire track really small, so winning players have to constantly pass the losing ones?
A Mario cart type game would be cool and all but we need something new and fresh. More power ups and more ways to play. Maybe there will be some gamemodes like king of the hill. Different maps that change the style of play. Less focus on generic racing and more focus on insane, super fun, all over the place, powerup-tastic gameplay.