Lately instead of the “common denominator”, such as “Asteraceae” for an observation with 2 photos showing 2 different of sunflower family species, I’ve been just IDing as “Life” instead. “Life” can be considered the community taxon, yes. It takes two IDers for a community taxon to appear on the right side of the page. Once two people ID as Life, and the “as good as it can be” box is checked, it’ll move to Casual grade.
not directed at you, but others:
For other discussion about these types of multi-species/photo observations, see https://forum.inaturalist.org/t/easy-way-to-mark-multiple-species-observations/278/ and this prepared response to the observer: https://www.inaturalist.org/pages/responses#multiple