I see that you are interested in making it possible to store modules (and templates?) centrally.
I am very interested in this as well, so I wrote a draft specification of how could this look like.
Here's a short version in French: Brouillon de spécification des modèles globaux/Résumé. A much longer specification (about 20 pages) is here, in English: User:Amire80/Global templates draft spec.
I'd love to know what do you think about it.
Feel free to comment and to edit these pages. If you have time to translate the longer page into French, it will be really great.