I am writing a new script library that will reference another script library.
Is a ‘depth’ of two libraries okay? I can see how sub-nesting these things could get messy.
In CS class they probably teach how to handle object code.
Any tips?
There’s no technical problem, other than making it difficult to embed the libraries. I know someone who does it 
Is there more to it than having a library “use” another library?
No.
I had an example recently. A series of scripts for a client included two libraries, one with Adobe-related stuff, and the other with miscellaneous ASObjC stuff in it. For one of the handlers in the former it made sense to call a method in the latter directly. I could have refactored my way out of it, but I didn’t see the point.
Roger that. Thanks for the info.