I'd advise against actually overwriting things
... You know, multiple template folders with an tick to the user to choose an available theme (kinda like we have now)
Well not actually realy overwriting files, but some kind of inheretance option, that certain files in the template directory are used, but if the are missing, the default files are used instead. This creates the option for partial templates / skins that work very well, and are still upwards compatible.
Did you check out the template/skin structure of b2evo? And if so, what you think of it?
