For the Bangle.js 3, I'd like to see stronger water resistance and higher build quality.
I'm disappointed to see my Bangle.js 2 suffer water damage even though I have never immersed it in water. An occasional splash from using the sink faucet was enough to make the device unresponsive and cause it to constantly reboot. This is surprising to me because IP67 rated devices are supposed to be protected from not just occasional splashes, but also water immersion of up to 1 meter for 30 minutes. The Bangle.js 3 should ideally have a 5 atm water resistance rating or an IP68 rating like some of the higher-quality imported watch models, or at least meet the IP67 standard more consistently.
The Bangle.js 2 has a body made of plastic, with sides that are easy to scuff and discolor. Some type of metal would be an improvement. The plastic button also feels mushy when pressed, and a more "clicky" button would be more pleasant to use. The electrical tape that covered the contacts at the bottom came off for me after wearing the watch for a month, and I'd like to see a more robust solution. I suppose the silicone protective cover would have made up for the plastic body and the electrical tape, but I didn't buy it at the time of my order since I've never purchased a case for a watch before and I didn't feel that one was necessary.
On the other hand, I'm very impressed with the functionality and ease-of-use of the Espruino platform. If a future Bangle.js model addressed the water resistance and build quality issues, I would purchase or pre-order it immediately.