This is such a neat concept! I love games that have an element of mastery to them. The stage the player goes through is the same every time, so a lot of time spent playing Cargo Airtime was in figuring out the perfect opportunities to rack up lots of points, instead of worrying about where obstacles and buildings are going to appear whenever I retry. This and the lack of any real bugs has kept me coming back to it a few times today to toy around with - great work!
Maybe having the cargo floatier than the ship to allow for more skillful and risky plays would help to really push this concept further. The gameplay, presentation and art is super cohesive and the music ties it up into a really fun little package.