But the interesting part is how to get the TDS archive
from a "wild" collection of files of a directory.
Indeed. For TeX Live, Sebastian wrote a nefarious perl script
(ctan2tds.pl) which attempts to deal with some of the *many* special
cases for packages, as well as some general rules. One of the places it
is weakest is documentation generation; so your improved versions will
be most welcome.
Guess I'm just saying thanks, and I'm looking forward to updating the
LaTeX in TL from these packages :).