Id been rereading Byrne's run on Superman a while back and there was an interesting comment Superman made, thet when he lifted something and flew with it that some "other strength" came into play. That really got me thinking and I started to add a flying stregth stat to my characters.
Flight is powered in many different ways, and the method of flight will determine how much you can fly with. For instance characters like Superman and Namor (c'mon, I dont care what any comics say, thos little wings on his ankles arent the source of his ability to fly) who fly though some sort of anbiguous means (psionic in nature perhaps) use either their strength or pysche values to determine how much they can fly with. The Judge decides which is most appropriate for a character and stick's with that decision, a player's flight strength is determined with the judge based on the characters origin (obviously Superman is well established as having flull strength in flight).
Magical, I tend to think magic gives you full acess to your strength in flight.
Telekinetic, I pretty much go by power rank or - 1CS less on this one.
High tech, I just dont buy Iron Man's tiny boot jets letting him lift 85 tons ( like when he picked up a mole man monster in Byrne's run on West Coast Avengers). Again I tend to go by type of propulsion used and tech rank of the device in question. Im my game Iron Man and Doctor Doom can both having incredible (40) flight strength. While Doom's armor is far weaker in terms of muscle power it is both nuclear powered and uses an anti-grav generator.
Wings this one's easy, its all about the characters strength here. If youre super strong, well so are your wings. Or if youre like The Osprey (the who?) who only has typical (6) strength, well thats all you can hold. In that case it doesnt matter how strong your wings are, if you arent strong enough to lift an object with your arms on the ground, you cretainly cant hold it will flapping your wings are whatever.
Well those are some of my base guidelines, there are certainly exceptions and mitigating factors for each, so nothing is stone and there's some room to play if needed.
Well hope thats some food for thought, comments appreciated!