'Strategic Air Command' was a good 'factional' movie - as was the later 'A Gathering of Eagles' where the stars were B-52s rather than B-36s and B-47s.
Otherwise ;
The Dam Busters
The Right Stuff
The Sound Barrier
I agree about the lack of story line in BoB. With such big name stars, you'd expect a reasonably definitive story line. However, truly excellent flying sequences (that was my Cranwell Sqn Cdr doing the opening victory roll over the French refugees) and a non-jingoistic portrayal of the Germans. Oh - and don't forget Susannah York wearing an RAF shirt and not much else in the hotel with Christopher Plummer!
Worst movies?
Anything made by computer geeks - such as the abysmal 'Pearl Harbor'. Storyline reasonable, but flying sequences dreadful. 'Tora, tora, tora' was infinitely better.
I've been trying for years to find 'Out of the Clouds' or 'Down from the Clouds' - something like that. It features James Robertson Justice as an airline pilot and has some excellent 'how not to do CRM' moments!