Following this with interest, having just built a custom driver of my own. USB flashing/configuration would be really cool.
The board looks great, and it does look very tight. I assume PCBWay didn’t raise any issues with clearances for assembly?
I’ll be interested to hear how you get on with the PWM input. I’ve not tried it, but AIUI the low pass filter makes it hard to fade smoothly between low and high ranges.
One of the things that motivated me was actually getting rid of the half-baked power bank IC in my flashlight, which was intended to power an accessory switch but has a slightly annoying standby current draw. Would be much less of an issue with a 21700 battery compared to 18350, but out of interest, how much current does the power bank IC draw when not in use?