I finally got around to publish the code: https://github.com/joemmert/SUhr
I wanted to change something on the Adafruit font I was using. Because it was pretty complicated to do this in the hex codes directly. Hence, I wrote a short python script to graphically work with these 5x7 fonts. However, after tinkering some more things got out of hand and I somehow ended up creating completely new font. Its not better than the Adafruit one (it's definitely worse), but now it's really easy to change things.
You find everything in the Fontgenerator folder. When you start the script it loads the current font state. You can choose the character number in the number field. Then you change something and close the window, and it automatically saves the changes. When you click the compile button the font is compiled into a header file that can be moved into the arduino sketch folder and done. So not the most advanced code, but short code and easy to use.
Also a short note on battery life: I'm currently using the second version every day, including the alarm to wake up. Without a lot of optimizations I currently have 10+ days of battery life (I always recharged at 3.35V). I guess I still can fiddle a little with the digital input buffer state to get some more out of it. Also BLE is currently still inactive. We'll see what BLE will cost in terms of battery life as soon as I cleaned up the BLE code.