Cool post. I have one small suggestion:
If you don’t want to type out %
or %:h
everytime you want to change to the current buffer or it’s parent directory, you should check out my plugin Fuzzee.vim which has a cool trick for doing :lcd :cd :e[dit] :b[uffer]
commands relative to the current working directory or current buffer depending on how you shape your arguments.
Cheers!