Is it possible to target components specifically? Hit the engine so you can catch up with them, target turret clusters to reduce turret rating etc

I can imagine a string of requirements for this, minimum range depending on the weapon type, arc of fire limitations and a reasonable penalty to hit.

Bombers would be easiest, lances also pretty easy, macros hard do to their scattering nature, nova cannons notably harder harder =P

well, while there isn't the possibility to say "I want to hit X with this hit" you can, should you cause a critical hit, apply critical damage to a component you know exists. While it isn't mentioned in the Rulebook (at least I can't find it right now > ) we always rolled 1D5 and applied the result.

Lances usually have a lower Crit-Rating (the amount of Degrees of Success the hit needs to be a Critical Hit) thus it is easier, and bombers have a fixed Crit-Rating of 4 (thus the Attack-Roll needing 4 Degrees of Success to cause a critical hit). Should you use Macrobatteries in salvoes, they can only cause one critical hit. Torpedoes use their damage-roll to determine whether it's a critical hit.

Please note you need to know which component to attack before you actually can influence it with a critical hit. This is done by the "Focused Augury" Action and any weapons shooting at you (including Torpedo-Tubes and Small Craft Hangars for Bombers and Fighters) are counting as Auto-Detected. However, some ships have special rules allowing them to choose the result of the critical hit (Tenebro-Maze and some weird Xeno-Tech I think) and some ships are even completely immune to Crits.

Hope that helped at least somewhat, in any case I suggest reading the "Starship Combat" Chapter in the Core Rulebook and the "Weapons of War" in Battlefleet Koronus

Edit: And, contrary to your assumption, Nova-Cannons are quite devastating and can, potentially, inflict far more crits then anything. Those things are brutal.