@cconverse I personally would go with a Document Set, working off the limited information at hand. Document Sets are incredibly powerful and I think you will find that this will be simpler to set up and in the long run you will have less management overhead maintaining this design. Setting up a new document library for every user would be quite a laborious task, and the only reason really I would think of to justify doing this was if you wanted to have different library settings in each for some reason. However this would again be a management nightmare! Document sets will also make you life a lot easier if you need to move the content or archive it, as this is what Document Sets are primarily designed to do. You can also pre-populate your Document Set with document templates when it is created, and have the documents inherit some or all metadata of the Document Set. If you could elaborate a bit more as to why you are considering a library for each person, maybe there are some reasons that are not immediately clear why a library would provide you some benefit.
One thing I would note though, is that if you are storing information about people in the document set, consider carefully WHY you want to do this. Is this legitimate document metadata? Or is this user information? If it is the latter, have you considered storing this information in either Azure AD (Or AD for on premise) or in the SharePoint user profile? Having this metadata on the user profile as opposed to on content will open up many more opportunities for you to access this data and use it in different ways, and is better design as well. You can secure the user profile metadata as well if this is a concern.
Happy SharePointing!
