I demand BangleJS3!

My wishlist:

1. OLED or (even cooler) e-ink
   
2. more buttons (useful but not strictly needed)
   
3. accelerometer with integrated step counter (Bosch has some really good ones)
   
4. PPG sensor with well documented HW and SW
   
5. multi color PPG (for example green and infrared) for oxygen saturation
   
   

I think that there is demand for really programmable smartwatches. So far the only ones I am aware of are yours and PineTime.