I definitely agree here. Weather effects should be something that is experimented with in the future builds. It does a lot of combating the problem of every air battle feeling the same and it could also be a ways of balancing some of the weapons and making them more unique.
I have some other thoughts about other mechanics to add as well.
-It might be worth removing rearming times entirely on the geoscape. If the intention is to make each air combat more unique and vary the weapons, planes, and tactics used in each encounter, having a rearming time that prevents the player from doing that seems counterintuitive. If rearming times were removed entirely, then the player could switch weapons on the fly and make air combat more dynamic and interesting.
-I find the initial air combat project rather strange. The player has not yet actually fought an air battle at this point, so lore wise it doesn't make that much sense for the head scientist to come up with missiles and torpedoes specifically designed to take out ufos if you haven't fought a ufo in the first place, and it feels wrong to give the player more options for air combat at the very beginning of the game as they have not experienced air combat yet and do know the ins and outs of it. This obviously is not an issue with veteran players, but this will probably be a minor annoyance for first time players that may join in open beta, early access, or even release. I think this project should be pushed back until the player has actually shot down a ufo once and acquired its datacore imo.
-I think there needs to be another slot on an airplane for misc upgrades to be placed on it other than just weapons and armor. This slot could add things like bigger aircraft radar, faster thrusters, slightly faster fire rate, esc. It would add a lot more utility, make each plane more unique, and make general air combat more interesting.
-Evasive rolls probably need to have another look at too imo. If the intention is to make air combat more strategic, then the current implementation has the same issue as Xen 1 where it rewards better reaction times and/or pause mashing to optimally evade a ufo's shots. This is probably another reason why torpedoes are generally prefered. Since torpedoes lock out evasive rolls in their entirety and outrange everything, then there is no need to worry about evasive rolls and do air combat battles with less effort. I can't think of any great solutions right now, but there needs to be some tweaks to this mechanic. Perhaps having a timer on a ufo's head to show when they are about to fire can ease the problem a tiny bit?