You state “I’m sticking with RDF as a core data format because I have a need to create extensible ontologies in a way that RDF is best at.”

But RDF isn’t a format. That fundamental misconception (not your fault) is the kernel of all the confusion and inadvertent misinformation about RDF and the notion of a Semantic Web.

Anything that isn’t properly understood will be confusing and complex.

RDF is an Abstract Language that allows creation of sentences/statements using a variety of notations. Sadly, after 17+ years, this isn’t how RDF is generally understood, hence all the confusion that inevitable boils down to RDF/XML vs Turtle vs JSON-LD vs many other notations.

Then you state “However, I am planning on transforming to other formats as needed like JSON-LD or specific “views” that mere mortals can deal with.”

Issue with the statement above is that JSON-LD is just another notation for inscribing RDF Language sentences to documents.

BTW — Graph Databases are a major distraction that have pulled off the opposite of RDF. By that I mean the are superficially coherent but technically inconsistent, as a paradigm.

Data is a Graph i.e., an Entity Relationship Graph made up of a variety of Entity Relationship Types (Relations). Thus, you end up with Graph DB implying that you have a Data Database?