This hierarchy represents the granularity of morphemic and phonemic symbolism:
Of these, Hangul (Korean) is usually attested as the only featural script (It was a deliberate construction, dating from ca. 1443). Contesting this view is the following article:
Primus, Beatrice. 2004. A featural analysis of the Modern Roman Alphabet. Written Language and Literacy, 7.2, 235–274
It's super interesting and one has to give the professor credit for trying to be systematic in her analysis. So I give it an A for effort, but…it's nonetheless unconvincing and historically naive.
The granularity of a formal (non-representational aka digital decomposable, not analog) script usually correlates to graphmic complexity in that characters that symbolize less granularity tend toward greater visual complexity; an inverse relation.