Not all state flags suck.
There are a few that literally have nothing wrong with them, and I’m not going to presume to come up with something better. New Mexico’s is one of them: It’s simple, it’s distinctive, it relates to the cultural heritage of the state, it’s easy to read from a distance, and it even translates easily into black and white (which is rare). It also gets bonus points for having the courage not to include blue – the most over-used flag color – at all.
Kudos to Harry Mera of Santa Fe, who came up with it almost a century ago (at a time when “cultural heritage” wasn’t even a buzzword yet).