Well to the TEC bombers being ineffective I did some number crunching

Note that all bombers and fighters of every faction have the same range of 2400. What I don't know is if the production time is the same for all races. If it were the same, then fewer, stronger ships would be more time effective than many, weaker ships. When I say squad health or damage, I'm just adding up all the ships in the squad together.
I'll start with
Advent.
Fighters#/squad:9
ship health:40
total health:360
ship repair rate:0.15
armor:1.0
ship dps:1.3(laser)
squad dps:11.7
Bombers#/squad: 7
ship health: 75
total health: 525
ship repair rate: 0.15
armor: 1.0
ship dps: 2.5(beam)
squad dps: 17.5
TECFighters#/squad: 6
ship health: 60
total health: 360
ship repair rate: 0.25
armor: 1.0
ship dps: 1.6(autocannon)
squad dps: 9.6
Bombers#/squad: 5
ship health: 100
total health: 500
ship repair rate: 0.25
armor: 2.0
ship dps: 3.3(missile)
squad dps: 16.5
VasariFighters#/squad: 4
ship health: 85
total health: 340
ship repair rate: 0.40
armor: 3.0
ship dps: 2.6(phase missile)
squad dps: 10.4
Bombers#/squad: 3
ship health: 140
total health: 420
ship repair rate: 0.50
armor: 5.0
ship dps: 5.7(phase missile)
squad dps: 17.1
So to sum it all up. Advent get many more strike craft, their total combined health and damage are the highest. Since each individual ship is weak (especially in the armor and health regen department), they are vulnerable to AoE strike craft skills like the KOL's flak burst.
TEC fighters are the worst by far. Their ships aren't any more survivable than advent's but they have the lowest dps. Their bombers are also the weakest, and only second best squad health. They have average regen rates.
Vasari win. Their fighters have average strength, a measly 20 less squad health, but 2 more armor than everyone else. Their bombers have high damage, relatively low health, but much higher armor than other bombers. They have the highest regen rates. They also use phase missiles which get the wonderful shield bypass bonus if researched.