This is on the verge of being outstanding! I’m just playing with it now but I love the idea that you not only take winds and temperature at a given altitude into account, but you take the fuel price as well. (I don’t know how you get the fuel price, but I will assume for the moment it’s close to correct.)
What I would like to see is a fuel stop planner. If I have a trip that requires a fuel stop, where should I stop? The planner can look at the fuel price and how much out of the way I have to go to get there and give me a tradeoff of time and cost. If get really ambitious you could compute the time for descent and climb based on field elevation.
I am really looking forward to trying this out in real life! Thanks a lot.