Hi!
I also think that the aircombat minigame needs some further love! Here are my thoughts:
I expect the Avalanche torpedos to be modified Harpoon missles. So they should be way more devastating than a simple Sidewinder against light alien vessels, also the larger UFOs should have way stronger armor, reducing incoming missle damage by 90%. This is because bigger UFOs tend to be more like flying ships fittet for space flight and atmospheric entry, rather than agile dogfighting aircraft. So you need a anti-ship missle and not a anti-aircraft missle, they cant do the job with their little warheads. In return hitting a dogfighter alien vessel with a Avalanche torpedo is as hard as hitting a thermal exhaust port on a deathstar.
Also here some facts ...
F-16 Fighting Falcon
Speed : 1.470 km/h (400 m/s)
Range : 4.220 km
Hardpoints : M61 Vulcan rotary autocannon, six AIM-9 Sidewinder* or two AIM-9 Sidewinder* and two Harpoon** missles
F-17 Condor modified against alien vessels
Speed : 1.500 km/h (415 m/s)
Range : 15.000 km
Hardpoints : XCOM autocannon, two XCOM Sidewinder*
MiG-31 Foxhound
Speed : 2.870 km/h (800 m/s)
Range : 3.800 km
Hardpoints : GSh-6-23 rotary autocannon, four Vympel R-33***
MiG-32 Foxtrot modified against alien vessels
Speed : 2.500 km/h (700 m/s)
Range : 20.000 km
Hardpoints : Two XCOM Avalanche** torpedos
*AIM-9 Sidewinder
Warhead weight : 9,4 kg
Speed : 3.000 km/h (833 m/s)
XCOM Sidewinder
Damage : 100
Speed : 3000 km/h (833 m/s)
Turnrate : 30 deg/s
Fire Range & Lockon : 3.000 m, 2s Radiationseeking
Modified XCOM Sidewinder
Damage against light armor : 100
Damage against heavy armor : 10
Speed : 3000 km/h (833 m/s)
Turnrate : 30 deg/s
Fire Range & Lockon : 3.000 m, 2s Radiationseeking
** Harpoon missle
Warhead weight : 221 kg
Speed : 860 km/h (240 m/s)
XCOM Avalanche torpedo
Damage : 200
Speed 8.000 km/h (2220 m/s)
Turnrate : 5 deg/s
Fire Range & Lockon : 7.000 m, 2s Active Radar
Modified XCOM Avalanche Torpedo
Damage against light armor : 2.000
Damage against heavy armor : 200
Speed : 1.460 km/h (400 m/s)
Turnrate : 5 deg/s
Fire Range & Lockon : 10.000 m, 2s Active Radar
*** Vympel R-33
Warhead weight : 47,5 kg
Speed : 5.500 km/h (1.500 m/s)
Advanced new XCOM Missle based on Vympel R-33
Damage against light armor : 400
Damage against heavy armor : 40
Speed : 5.500 km/h (1.500 m/s)
Turnrate : 15 deg/s
Fire Range & Lockon : 7.500 m, 2s Halfactive Radar