So after couple "experiments" I may have found battery life lasting a day.
Brightness: 5-1
Wake-up Gesture: ON
BPM measuring/hour: ON
Full charge - 7:00 am (9/12)
37% - 10:00 pm (9/12)
15% - 10:30 pm (9/12) (turned brightness from 2 to 5)
You can customize watch faces on mrtimemaker website. In fact, you can make your own too.
I am going to design a watch face similar to Montblanc TimeWalker Urban e-Strap on GearWatchDesign program.