Hmm. The centrality of the chorus would provide a foundation. It gives us a sense of how strong the voice of the community was in the polis. After that, the way Aeschylus allowed his play structures to develop provides a parallel with the larger city-state; he allows individuals to emerge over time. The content of his plays, with their blend of history and what we call myth (but which would have been shared belief for a lot of the audience—religion), but through a lens that allows him to comment on contemporary action, gives a good sense of how past, faith, and present interweave in the polis.
Now, within "The Frogs," he claims to strengthen the morality of his fellow citizens.