closing thiis (sorry, took a while ;)
neinp for sure needs more documentation, but i don't think copying commentary is the right way to do so. the best would be more example fs, not only rssfs. unfortunately my other ones are really hacky.
media size is sometimes reported as "all 64 bits set to 1", which is wrong and breaks.
some scripts assume content-disposition some don't. maybe just do a customization doing symlinks?
proc and sys are already mounted, shm is required for python "threads".
some scripts need stuff like /proc, /sys, /dev/shm