I designed a new board that uses 2 CR2032 batteries and a WS2812b/Neopixel. I had my concern about how much the power draw will be, but I have been playing with it for over 3 days and it seems to work fine. I forgot to add a diode to drop the voltage to the ATTINY85 (safe levels are 5.5V), but there are no glitches.

There are programming headers now for easier reprogramming. However it is not compatible with a breadboard yet. I used one of my headless Digispark devices to program the Breathedot.

The nice thing about his new Breathedot (or BreathePixel?) is that the RGB colors are really pretty and the board provides more space to add other things like sensors or a IR receiver or light sensor.