Multi site for directories & wider client use

Hi all -

I’m new to using Kirby’s multi site feature, and had3 questions I was hoping someone could shed some light on.

Firstly, I have a client that has various internal departments they wish to have their own directory and their own style (can be some very simple stylesheet overrides if need be). An example of the url structure for a case-studies page would be as shown below:

With the example on the multisite page, only domains are referenced in the config, but could I use this to add the directories and have the same domain as above? Or is there a better way to do this that doesn’t require licences for every department, as it’s the one company.

Secondly, is there a way to have these sites all accessible via the one admin panel?

Now for a 3rd question. After looking at the multisite docs, I’ve been wondering if anyone out there uses this to run a single install for ALL of their clients? One on hand this seems crazy to me, but on the other it means I can have one single kirby install that i keep updated, and all client sites site within this, with their own site files, own plugins, own content…

Has anyone done this or can anyone see some big downsides?