I will be taking tier 4 as a basis due to not so much difference in stats between tier 4 and tier 5 fighters and the problematic "no reason to unlock t5 whatsoever".
In tier 4 module screen says the following;
-1000 DMG per second
-1000 HP per fighter jet
-2000 KM roaming range
-80 second cooldown time
Before making any suggestions, lets talk about problems here.
In game 1000 DMG per second translates as 1 fighter doing 187 damage with each hit, but not all fighters can shoot at the same target even if there is only 1 target. This is due to their weapon range, turn rate, and their distance to the enemy
If a fighter detects an enemy ship they start turning also moving towards them, but they turn so slowly before they can get the enemy at their cone of fire they get too close so they only have 1-3 seconds of opening to fire which cripples the damage output, hence turn rate must be superior to their overall velocity
Also if you deploy fighters early on before engagement they fall behind unable to follow you fast enough (1-2 km behind) Hence their velocity must be increased
And lastly their cone of fire + range will always be a problem since they dont have a very smart AI nor roaming range my suggestions as follows;
**(Tier4) (Tier 5 should be improved taking Tier 4 as basis..)
-Damage per hit 220 from 187
-2000 roaming range + 1500 weapon range / Total of 3500 maximum firing range based on carrier itself
-50s Cooldown time from 80s (80 is too punishing with nukes, cluster nukes, torpedos, siege modules..)
-Cone of fire x+30 (Their current cone of fire feels like 30' from my multiple testings in proving grounds gamemode against bots)
-Their max forward speed +%25 so that they can catch up to the carrier (I was using T4 Oberon Carrier at full speed with no speed buffs or speed effecting officer briefings yet they are usually stuck 1-1.5 km behind.
-Their acceleration must be doubled, their reaction time is absolute 0
-And most importantly their turn rate must be %200 OR %250(due to velocity increase which can cause further turning problems in CQB battles) besides they are fighters should they feel like medium corvette of oberon which is faster than heavy corvette yet sluggish than a destroyer when it comes to turning