[Jeroen]

still think defining all packs required by the skin in addon.xml should be the way to go.
when installing a new skin, all required packs need to be auto-installed imo.

I agree. I think the focus should be to make it easier for the end-user in this regard.

For instance, I provide skinning support for several add-ons in my skin. While this all works basically I would prefer to have the code for these add-ons separated from my main skin code.

An example: recently support for the subtitles add-on in my skin broke because of an update of the add-on itself. In that case I have three options:

1. Make the user wait for an update in a milestone release of the skin;
2. Push out an update of the entire skin, just to fix one issue;
3. Put up separate xml's for people to drop them in the skin folder.

None of which are what I would call userfriendly. I understand using the repo would provide a way to push smaller updates but in my understanding the point of a repo is to use that for big(ger) updates.

So, if these were separated into separate add-ons / modules to the skin I would be able to update them separately and push a small update.
Basically upon installing a skin, the user could be asked to do a "barebones" install (just the skin), or select optional extra components that provide skinning support for add-ons, as not everyone uses (thus needs support for) the same add-ons.