WOW!
Great work & well described 
How do you configure f.e. the calendar, without bluetooth or something? Or is it just showing the days?
Your first version looks quite similar to my first smart/fitness-watch (Garmin Vivoactive).
It´s also a logical combination of battery-life and features. The display was not great (agains all the fancy samsung or apple watches) but it survived more than 14 days, even with Bluetooth (Low Energy) and GPS on sport activities.
Since you can develop Apps and Watchfaces yourself, I´d never challenge myself to create my own hardware. I´m too bad at that 
But what you have done on that tiny space, is amazing!