...how to best design a data structure which can match the requirements necessary and be future-proofed enough

Excellent question!

Fortunately, there is also an excellent answer!

The relational view (or model) of data described in Section 1 appears to be superior in several respects to the graph or network model [3, 4] presently in vogue for non-inferential systems. It provides a means of describing data with its natural structure only -- that is, without superimposing any additional structure for machine representation poses. Accordingly, it provides a basis for a high level data language which will yield maximal independence between programs on the one hand and machine representation and organization of data on the other.

Further reading