Basically I want to have a directory structure not unlike “garrysmod/addons/myaddon/subaddon/lua/foo/bar.lua” and still be able to include bar.lua without resorting to RunString or something.

models/materials would be nice too

I’m not sure that’d be feasible. Why would you want to?

3 things:
to allow wiremod to be checked out in one piece instead of 3 (wire, wire model pack 1, Adv Duplicator)

to separate the various parts of wiremodextras, so they’d be more maintainable

for my own SVN, so I can still easily make releases and still have to only check out one repository
it contains 4 small components atm, of which 2 were released separately already, but which aren’t really big enough for an own SVN (1 lua file+info.txt basically)