I agree that this is an important feature - however, it is not new!
A centralised seed file has been discussed in detail for at least 10 years, on this an other Graphisoft forums and even in person during various technical visits by Graphisoft HQ.
@Minh > how does this wish list work, is there no cross check for existing features... and if this wish is not already on the list, why?
Btw. the BIMCLOUD server is the perfect location for this centralised SRF or seed file.
Regarding, the OPs idea of the sync being bidirectional by default is a good idea, although I am not a friend of micro management, a SRF connected / wired to multiple or all your project files and which can get updated from anywhere is a bit of a risk factor... maybe if it was limited to a specific BIM Manager role which controls the distribution process?
Also in our experience, across all project sizes you will always have project specific attributes that get added as you go along. Again this is where we had suggested in the past that the BIMCLOUD server could facilitate the QA process by comparing the attribute set in a given file agains such a sees or SRF file, highlight the differences and repeats across projects, which you can then add to your base SRF file for future projects.
But either way I would be more than happy to have a very simple implementation of this as a starting point.