This is great and I've been looking for something like this for a long time.
The only thing it needs now is to allow you to better refine the time period (e.g. only weekend trips, or only two weeks in October, etc). As it is now, it's great for people with a month or more off of vacation, but doesn't quite do it for the rest of us yet.
Well, it gives a rough order of magnitude, and might encourage people to consider destinations that they would have thought were too expensive. As in "Gee, I was going to go to Salt Lake City, but it turns out I can get to Lima for the same price..."
The only thing it needs now is to allow you to better refine the time period (e.g. only weekend trips, or only two weeks in October, etc). As it is now, it's great for people with a month or more off of vacation, but doesn't quite do it for the rest of us yet.