More of a cosmetic/nice-to-have than anything necessary this one, but:
Could we have some improved automatic flight number selection options? Right now it will select the next number after your highest flight number, even if you have lots of empty gaps.
Perhaps something similar to the way aircraft registrations are done now (next available registration starting at a certain one per aircraft), but for bases - so for example I can assign flight numbers starting at 500 to this base, and 1000 to that base, and it selects the first unused one from there?
There may be other useful ways to do this but that's the one that comes to mind first.