Thanks for the suggestions -- they're always welcome (otherwise, I have to try to guess what people want).
I know that the big map needs some usability work. It was one of the first pieces I wrote, and I haven't done much with it since -- I'll try to get to it soon.
For private/public airports, there's a primitive tagging system for airports. Right now, the tags aren't very popular, but I hope that members will start tagging airports soon. I've tagged CA/US airports with customs, etc., to get started, and I've tagged a few airports with tags like "military" and "private", but that's a drop in the bucket with nearly 40,000 airports on the site.
