What I would like to do is use WP Multisite and have a separate database for each site as opposed to multiple tables. The idea behind this is to keep the sites separate and running fast as running a few hundred sites on a single database would begin to become slower than if they were each on their own database. However, it would still allow me to update all sites core wordpress files in one location.
I know there is sharedb, hyperdb and multi-db plugins but as far as I am aware they will use multiple databases but not spread each site in its own database.
Some help pointing me in the right direction would be appreciated