The UniMorph Schema includes the features necessary to distinguish all these categories, which are marked by surface contrasts in each language and are not decomposed further in any natural language.
5 were a language to be discovered that distinguished a blended dual-trial (2/3) from singular, paucal, greater paucal, and plural, the UniMorph Schema would combine the minimal dual (exactly 2) and trial (exactly 3) features together additively to annotate the blended category (as DU+TRI).