I'd suggest a small change, though: make it a runtime package so that users don't have to add the extra path to their projects. Adding extra paths to projects seems to be prone to unexpected compile-time "bugs"
Hmm... I thought adding library in a form of plain source units is a most basic operation, even for novice.
And I doubt someone will benefit by adding extra package instead of extra path to a project.
Both is done by selecting files/dirs in GUI. And the worst "bug" you can get is "Cannot find xxx used by yyy",
which is pretty simple to fix: invalid paths are greyed.
Also, non-Lazarus environments (pure FPC, another Pascal compilers, m.b. Delphi) will not be affected by this feature at all.
So honestly I think it's overkill. But if someone want to improve it, you're welcome. Fork it, or I could even give you an access as collaborator.
But I'd better write documentation and better samples.