How about expanding on the houses idea? Light houses were mentioned. Well, that's a "house". And a school house block? And a Post Office? (okay, not as house but hey.. ). Make it a "Town" Quilt. School, Post office, Church, Mosque, houses, lighthouse (make it a town by the sea) Police station, Firehouse, Library, Doctor office, a park, a marina, etc.?
Something beyond stars and churn dashes. But still do-able for beginners willing to give paper piecing a go.