Software-wise, nearly everything is completed. Now it comes down to making my wearable, well, wearable.
After some test fitting I decided that it would be better (for now) to have all the guts of the project tucked away, only leaving the neopixel and sensor on my wrist. Even with everything crammed together, it's just too tall and wide to be one piece. Obviously this isn't ideal, and I have a few better solutions once I can test it some more.
The sensor and neopixel connect to the rest of the components with a 7 pin cable normally used for balance charging 6s lipos. An added benefit of this is that it's modular: I could theoretically unplug the neopixel and connect another module (gps, accelerometer etc) and I'll already have all the pins I need (3.3v, raw V, GND, SDA, SCL, D6, D7) in place.
I quickly sketched an enclosure in autocad and cut it out of 3mm carbon fiber. It actually turned out a lot better than the hackjob I was expecting it to be.