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
They do need to fix the damn controllers, but even if they didn’t drift the sticker are so tiny and it’s not a comfortable controller at all.
I just use then when I need them (for Switch sports, for exemple) but everything else is 8bitdo controllers and the pro controller, which are so much better.