At first glance, the lasblaster looks relatively weak, but it's range of 24" can bring about some surprising results. Use large squads of Swooping Hawks because massed firepower causes a lot of armour saves.

The Swooping Hawks are able to deep strike no matter which scenario is played and this can be useful in "cleanse" and "take and hold" missions.

Another use for deep striking Swooping Hawks is to deal with deep striking enemy troops such as Dark Eldar Scourges. The enemy deep strikes and then shoots but can't assault. If they are powerful in hand to hand (such as terminators), you can deep strike your Swooping Hawks behind the enemy (if they landed behind their target) and shoot them.  This can sometimes cause the enemy to fall back, but the main reason is to cause a diversion to distract the enemy away from its target.

If the enemy's target is within assault range of their deep striking troops and you don't want your troops to move (for eg. if they were Dark reapers or Rangers), you can, if you're prepared to sacrifice them, land the Swooping Hawks in front of the enemy, to take the assault. If the Swooping Hawks are defeated and break, they will run back through your troops and anything chasing them will be able to be shot at as they sweep after them. Remember, that if you can't fire a move or fire weapon, it is useless.

Another use for the Swooping Hawks is to harry heavy weapons teams that inhabit your enemy's back lines. Swooping Hawks can cause quite a bit of consternation when they land in the back lines of Orks and Imperial Guard. If you take a large squad, it will be able to endure quite a bit of punishment. Having an Exarch in the squad can also help in hand to hand.  While the enemy is shooting at the Swooping Hawks, they won't be using those spent shots on the rest of your army.