multitude, crowd, masses, public
众 centers on a large gathering of people: a multitude, crowd, or the public masses. It conveys the idea of many individuals together as a collective.
众 is a compound of three 人 (person) glyphs, visually representing many people together. It is a straightforward ideograph for a crowd or multitude.
Three people (人) stacked together: one on top, two below. Picture a crowd of people gathering, forming a multitude.
For ギン, imagine a huge crowd of people all grinning at once: grin -> ギン, and the multitude smiles together.