Despite the lack of public updates, I have been putting some time into this.  I don't plan to do much more with the revision 1, it was awesome to get something done, but there were few i's dotted or t's crossed on that design - it was an MVP and a learning experience, more than anything.  Rev 2 is in process now, the main changes being a complete redesign of the voltage frontend, functioning resistance protection, and a proper board, with half decent power management, for the display.  As might be gleaned from the pictures, I'm also hacking together some equipment to test both the temperature stability and input protection.  Before making a board with the final form/fit/finish, I've gotten some test board made - thank you to Pcbway for sponsoring the boards for this project! they've been fantastic.  These have a couple different footprints and designs, and switches to start getting some real numbers on things like leakage.  

Edit

Oh I also finally bought an oscilloscope with a function gen and made a test script to characterize the frequency response of the frontend.  I'll do a more detailed log later, probably after putting out the video.  Also I'm like 2/3 of the way through a video going through all the details in the design and circuitry of both rev 1 and some changes coming in rev 2.  So, look for that soon.