Drovers only. Drovers beat everything. They are far more fuel and supply efficient than cruisers or capitals, and depending on how many of them you deploy, then can handle anything from occasional run-ins with pirates, bounty hunting, to farming AI cores.
https://sectorloadouts.info/view/EAYxwcBdjNR9YfwrGStart by shopping at Tri-tachyon and Persean league stations for Drovers, get at least 5 Drovers each with 1 Broadsword + 1 Talon, controlled by cautious/steady AI officers with carrier skills. This will be enough to take down pirate bounties up to 100k. Then add more Drovers as you find or salvage them. About 20 Drovers should be enough to take down any bounty fleet even without any officers or skills. Then hunt down redacted fleets to salvage their Spark fighters, which are the best fighters for the Drovers.
A fleet of 10 officer controlled Drovers and 1 player controlled Astral will comfortably handle any bounty mission. Recommended bounty hunting setup is 10 Spark Drovers +1 Longbow/Cobra Astral + 1 Phaeton + 2 Colossus
Note, do not deploy a warship with the Drovers, as there is an AI issue that causes your carriers send all fighters to escort the warship instead of using them for strikes. Also, Drovers are no good vs starbases, if you want want to take on a starbase, you should manually pilot a Heron or Astral with bombers, as long as it's not a warship, cuz then you will run into the fighter escort problem.
Proof of effectiveness, 20 Drover fleet destroying pirate starbase and 616 pirate ships:
Additional recommendations:
Get the Coordinated Maneuvers and Electronic Warfare skills so the Drovers can more easily stay out of range of enemy gunfire;
Get the Fighter Doctrine skill to improve fighter replacement rate and reduce crew losses;
Get the Industry skills that improves equipment salvage rate and ship salvage rate, so you can save money by salvaging enemy Drovers and fighters
Have a crew transport ship with your fleet until you have equipped all Drovers with Spark fighters, as Drovers don't have much spare crew capacity, and fighter losses will result in crew being understrengthed if you do not bring spare crew;
When you are near the endgame, and don't care about fuel consumption any more, bring 10 of Paragons just to boost your fleet deployment points.