Very cool, but I'm not clear who your site targets. That price is amazing but the itinerary involves a lot of flying around on terrible airlines. I usually have a lot of restrictions: I want to fly on these dates, with the fewest travel hours possible, on good, dependable airlines. How much leeway is in there to save money?
Less leeway, but flightfox is about saving you time and money. Even if you build a 6-continent itinerary with a lot of restrictions, it will take many hours. The tips and tricks the experts provide, even for getting on better airlines or other perks, really comes in handy. There are of course sometimes we just can't help. That's normally with simple itineraries and inflexible flyers.