Here's an interesting thread on some various loadout options. Considering how many options there are, it may be more feasable to alter the way in which loudouts are selected: chose by hardpoint/bomb-bay.
http://www.ww2aircraft.net/forum/tec...uts-14154.html
For instance, in a Ju-88, the player could chose the loadout for the front bomb-bay, and leave the rear bay empty, instal a fuel tank, or more bombs!
For planes like the TB-3 or Pe-8, the player can chose whether the bombs are placed internally, externally, or both.
And finally, for aircraft like the P-47, the player could select extra ammo, or remove a pair of guns, or alternate between a couple belting patterns while choosing a bomb load for each hardpoint: frag bombs, 250lbs, 500lbs, 1000lbs and various drop tank combinations.
This could also allow asymmetrical loudouts of some Japanese fighters which sometimes carried a bomb on one wing, and a drop tank on the other.
The drop-down fields could be labelled "Guns" with a list, "Hardpoint 1" with a list for the forward bomb-bay or right-most hardpoint, "Hardpoint 2" with a list for the rear-bomb bay or middle harpoint, and "Hardpoint 3" with a list for the external racks or the left-most hardpoint.
The main advantage is being able to pick the loadout the player needs without resorting to an extremely long list in which it may be annoying to find the combination that one wants (some aircraft have over 30 options I think)