These assume all turrets are available if desired.
To help provide a concise idea of a turret's strengths, and how to use it.
Basic: Anti missile frigate, general purpose cheap turret (in both resources and knowledge). Place between wormhole and command station.
Sniper: Maximum range instant damage. Super effective against raid starships, bombers, and melee craft. All these vessels somehow defeats your shield. Place on outskirts, unless using a single shield defense, then maybe place just outside the shield.
Spider: Like sniper, so you can double your cap of that function. Also able to neutralize most fleetships in a single shot through engine damage. Due to cost, would suggest to always keeping them on outskirts for protection.
MLRS: Anti-fighter. Anti melee. Can outrange most things. Ineffective against armored vessels.
Missile turret: Anti-bomber. Wide range of damage. Effective vs raid starships. Usually can cover the whole distance between wormhole and station with plenty of room to avoid passing attacks.
Laser: Anti-bomber. Anti-starship. Place where the enemy will be a while. Like wormholes or around station bubble.
Lightning: Localized attrition. The harder and longer the fight, the stronger they get. Always combine with gravity turrets or tractors.
Flak turrets: Short range. I use them exclusively at wormhole entries. The text doesn't explictly state it but I think they have AoE like grenades, or maybe an even shorter ranged version of it. with AoE they get much more powerful and can dispatch some units themselves.
Counter sniper: Never have used them. Ever.
Tractors: Can be placed at wormholes if mines aren't used much. Doesn't lose effectiveness under a shield if it can get units from outside bubble.
Gravity: Effective regardless of numbers, making it very handy as difficulty numbers go above 8. Doesn't lose effectiveness under a shield at all. Higher marks may provide a stronger benefit then first indicated as it's power increase is not as linear as other turrets.
Tachyons: I always invest in military stations, making these redundant. Can't comment.
Heavy beam cannons: Very effective if combined with gravity or tractors so as to maintain "bunchiness". Not enough in caps for my taste on their own, but if doing fallen spire then highly recommended.