This is a weird one, but I’d love to see a reimplementation of the sensor bar. The gyro controls haven’t cut it for me. I like how the Wii U game pad had the sensor bar built in to the bezel. The real engineering nightmare would be squeezing IR cameras into the top of the Joycon
For me it’d be analogue triggers. I think a scroll wheel could also be cool and unique controller input.
A scroll wheel could definitely help with totk nav. Especially if clicking it would allow you to navigate to the next page of items.