Way cool track bike trip! The idea is cool and the execution sounds creative. You must have the satisfaction of a grand adventure.
I presume you rode fixed gear? Brakes? How'd you carry tarp? What gear did you carry and how'd you carry it?
I keep wishing my Garmin Vista HCx will be easier than stopping every 3rd turn to put on reading glasses and reading a map. Last year Garmin recalculated umpteen times when I veered off it’s high traffic Rt. 128 service road routing. This year my Provincetown trip with map and GPS took us off course only a few times. In terms of infallibility, it was three way tie between map, gps and my judgment.
Last year I used a new modern, screened tarp tent with sleeping bag, change of clothes and can opener. Light weight touring is a blast and your Boston-coastal version ambitious. I like your inventive train portion and night time bolt home. Lights?