Windows 11 OS File system layout, and survey of write-ablility requirements? [closed]

So, first off, there already exists this post:

Constructing a readonly Windows system partition?

And I would like to ask for a bit of flexibility, while technically, this is essentially a duplicate, I think that I can make this slightly more specific in scope (windows 11) and also practically restart the discussion, a decade later, as things have certainly changed since then.

Also, I understand that VMs, (and also network disks) can support thin provisioning and sharing. But this is asking for something else (I want to say that when I have tried this, it seems like it actually ends up using more space as the OS will generally try to overwrite the files on the base image.. but that is only my anecdotal experience…)

What file locations actually need to be writable by windows 11? Is there a manageable set of directories that write access could be limited to, especially in a stripped down version of windows like through https://github.com/ntdevlabs/tiny11builder ?

Of these file paths, which can be moved (or have the location controlled, or indirected?) like could these paths be mounted (or just referenced directly) over SMB/CIFS? Can `subst` be used to link them from a wholly read-only partition?

Also, it would be generally interesting to know how a Super User could leverage the windows file-system layout to create their own custom system…

So, Unified Write Filter (UWF) exists, and may actually be the best options, but I think if it would be used naively on the root, then it have the same problem as VM shared disks… I think restricting and controlling the write-ability, where possible, rather than permitting it through virtualization may help control the space requirements…