What makes a fun kart racing game?

Hey Reddit,

I am an indie game developer, and am currently planning on making a kart racer for iOS/Android devices. As you have probably noticed, this genre is kind of a lost art on these portable devices. The few that are available are either well planned but poorly executed, do not have many fun power-ups, or just have horrible controls.

You, the Reddit community, what would you like to see in a kart racer for portable devices? What makes for a good racing experience? What type of controls do you prefer? Power-ups? Tight or loose power slides? Art style? Any kart games that do play well on portable devices?

Any amount of information would be greatly appreciated. I will also try to answer as many questions as possible. Help to make the best portable kart racing experience!