By the moment is very simple, I just replicate the data of file based users to the database using database toolkit functions of kirby. I will try to find some time to finish it.
haha, no rush! no good work ever comes from rushing, it’s jsut interesting to see different takes on the same task. 
Ok, I’ve got it working!
I added an optional DB “Extension” I’d love some feedback!
Full support for all special fields as well (like structure) and user blueprints!