I don't think it makes sense to compare abstract geometric flags with flags based on seals. Yes, geometric flags have elements that can be easy to recognize even when adapted. I think the Maryland flag is a good example that even if a flag is re-mixable and easy to recognize, it can still be hideous. Pink polka-dots on blue-green plaid would be versatile and recognizable too.

Flags based on seals aren't meant to be hung from coffee shops. They are meant to be displayed and viewed up close so you can see the detail. And in this genre I think Virginia's is best. It's got violence, nudity, and awesome latin phrases: Sic sempre tyrannis - "Thus always to tyrants". What more could you want?

https://en.wikipedia.org/wiki/Flag_and_seal_of_Virginia#/med...