Generally i always found it a bit counter-intuitive how fighters work - they remove enemy attack craft on a 1:1 basis. Normally, if e.g. 5 fighters are in combat against 10 enemy ones of the same quality, then they wouldn't get wiped out and cause five casualties to the enemy at the same time, but only about two or three.
When one fights with 2:1 superiority one can expect to lose only about 1/4 of the own strength, if one fights 3:1, then one usually loses only about 1/9 and so on.
In BFG however casualties of fighters are always 1:1. That's explained with the victorious fighters having to refuel and re-arm, but that kinda seems like an excuse to me.
As a consequence, there is absolutely no reason to field fighters in waves. One can achieve the same effect when one brings two times one fighter against the enemy as if one brings two fighters once against the enemy. I think the game is foregoing a but of depth there, by completely neglecting any advantage to fighter waves bigger than one.
Enough with the motivation, that's my suggestion:
Normally, if a wave of fighters attacks enemy attack craft, then you'd normally remove as many squadrons from both your own and the enemy wave as there were fighters.
A wave of 5 fighters against a wave of 3 enemy squadrons would result in both sides losing 3 squadrons.
I'd suggest to modify this procedure so that the player with the superior wave (the wave with more fighters) gets to roll as many dice as he has squadrons of fighters more than the opponent's wave has squadrons (perhaps both fighters and others, perhaps only fighters count, that's yet to be determined)
For each 4+ he can keep one of the squadrons which normally would get removed in the game.
So if a wave of 5 fighters attacks a wave of 3 fighters, then the player with the 5 strong wave gets to roll 2d6. For each 4+ one of his squadrons which otherwise would get removed can stay.
It's simple and effective:
E.g. if one fights with 2:1 superiority, then one has as many more fighters as the opponent has, and with that one gets to roll 4+ for each own normal casualty. This reduces the own casualties to exactly the 1/4 of the own total number which would be expected in a "real" 2:1 combat:
8 fighters against 4 fighters would result in 4 chances to roll 4+ to keep a squadron in the game, 2 casualties in average. One roll for each squadron which otherwise would get removed.
Of course, how other attack craft than fighters would work in this would yet to have be determined, as well as torpedoes. But i think it's a good way to make fighter waves have an actual purpose.
Other attack craft e.g. could count as half their number in fighters for determining the number of rolls. A wave of four fighters against a wave of four bombers would count as fighting two fighters, so they get two rolls. That'd mean that in average one fighter survives, as bombers remove fighters on a 1:1 basis just like other fighters do, they just count "halved" for the number of rolls the fighters get.
Or bombers and so on don't count at all for the number of rolls one gets. A wave of four fighters against four bombers would get a full four rolls of 4+ to keep fighters in the game. This would create an imminent benefit in including fighters in bomber waves, by significantly increasing the number of casualties the opponent has to expect if he attacks the wave with fighters.
Simularly, torpedo volley which count as a single fighter for the purpose of casualties, can count as their strength divided by two, three, four or even five for determining how many rolls the fighters get.
So a wave of four attacking a torpedo volley would have a good chance to wipe it out without any casualties, whereas a single fighter would get removed along with it.
Generally, in regards to the effect on the game balance, this would mean that the player with attack craft superiority has to dedicate some fighters to cleaning away the enemy fighter screen instead of just swamping him in bombers which so far fight just like fighters when they encounter these. If he doesn't do that, then even an opponent who is inferior in terms of carriers can put up a good defense against bomber rushes by taking advantage of this bonus against bomber squadrons.
I think it'd add a significant portion of depth to carrier battles without making the game much more complicated.