This all depends on whether one views the examples of Daas Yehudis mentioned in the Mishna as fixed or as something that can change depending on the tznius standard of frum women in each time and place.
If they are fixed, then Reb Moshe’s disagreement with the Chasam Sofer is limited to what Reb Moshe was specifically mattir. If, however, Daas Yehudis is different depending on the time and place, then once one argues on the Chasam Sofer (who held that every hair must be covered) there is no limiting principle beyond substantial coverage and the norms of the community.