I thought phase missiles and armor were the only things that would improve for the Vasari fighter/bombers. Which always annoyed me, because you can only get the 20% damage bonus on phase missiles, and it takes a lot of pre-reqs to get there. I've had games as Advent where I'm frustrated beyond belief that the enemy's phase missiles seem to be acing my hull, but even when I missile swarm as Vassari I rarely notice a huge boon to the phasic missiles. If fighters use wave, that would make me very happy.
Here are the stats for fighters after being fully upgraded, not including auras or carrier abilities:
Vasari
Hull: 105.4
Armor: 7.5 Very Light
Damage: 36.9 Phase Missile w. 25% chance of negating shields
Speed: 4320
Squadron Size: 4
Advent
Hull: 50
Armor: 4 Very Light
Damage: 20.6 Laser
Speed: 4000
Squadron Size: 9(10 for Hangars)
TEC
Hull: 76.8
Armor: 6.3 Very Light
Damage: 24.4 Autocannon
Speed: 4000
Squadron Size: 6
As you can see, it would be very hard for fully upgraded Advent or TEC fighter squads to defeat a fully upgraded Vasari fighter squad in direct dogfighting(or rather passing and shooting every 12 seconds), mainly because of the Vasari fighters' armory and speed advantages. Higher raw DPS for Advent fighters would mean, though, that they are better than the TEC and Vasari fighters in interception and destruction of enemy bomber squads. For strafing attacks on light armored ships, the Vasari fighters have the advantage again in that if even a single fighter in the squadron punches through the target's shields(and mitigation), the squadron inflicts more damage than an Advent fighter squadron attacking the normal way.
Why would they be better with Wave Cannons anyway? All that would do is make them slightly better at shooting down bombers, but worse at strafing LRM/Scout/Siege ships.