(1) and (3) also apply to Egyptian hieroglyphics... They're pretty generic design decisions for languages with composing characters. And (2) is just a syllaba

(1) and (3) also apply to Egyptian hieroglyphics... They're pretty generic design decisions for languages with composing characters. And (2) is just a syllabary, which is certainly not unique. Any composed syllabary that is meant to read left-to-right, top-to-bottom will likely meet (1) and (2).