My favorite is the hammerhead, without a doubt. Though I haven't tried too many, because the Hammerhead is already everything I could ever want.
Fast enough (even faster with Augmented engines), decent shield, two frontal missile launchers, two frontal guns, and four PD spots.
On half damage, I usually ram my enemy with it because it's shield is pretty amazing at half damage. Though it seems like 100% damage makes that strategy much more risky (though there was this time where I rammed a corpse of a ship into the enemy...
). Otherwise, I unleash dual Sabots on my enemy, shattering their puny shields while simultaneously getting in close with the main guns. Just like that they're overloaded, and they've got armor damage.
With all PD spots armed, you can put out very serious PD fire at the direct front of the ship. 4 burst PD lasers=3 destroyed missiles if they're in a row. In addition, they can all go on the offensive against the target in front of you.
I usually can cause
very serious damage with that ship. I love it to bits.