Hardware: Ideas for further development of hardware interface

While researching GPS time related questions I have come across a few interesting projects which have some very useful solutions. One of which is a supercharged version of our hardware interface with backup RTC and battery, 18650 with BMS and more. Post about it can be seen here

Another approach is a but more minimal in terms of size, useful code done there and uses an older version of TinyGPS library. Can be seen here