This has been mentioned here and there but I'll like to consolidate what I'm looking for out of it.
At it's most basic I want to be able to customize targeting/action priorities for every fighter, ship and turret.
So let's say a heavy fighter with coilguns and anti-ship missiles for instance would be something like this:
1. Engage Heavy Frigates, Light Destroyers. Maybe for some reason I don't want them to engage Frigates and Medium Destroyers so let me customize it's specific target set. Bonus for even allowing me to target specific ship classes. Maybe I want them to hit a Broadsword but not a Fenrir for instance.
2. Defend the flagship, not sure if fleet leader equals flagship or whether it depends on what you're piloting. Or maybe I want it to defend a specific ship type or class, like defend a frigate or defend a Caiman. Or maybe even defend a specific ship, but I don't know how you'll do it if the specific ship isn't deployed or is destroyed. But you get the gist of what I want, until we have carriers where they can land and stay safe, I basically want them to defend a ship where they are safer than hang out somewhere dangerous.
And while defending a ship, I might want different targeting priorities too, like I want them to engage heavy fighters first, then frigates, then medium fighters or whatever. Basically a separate list of targeting priorities here.
3. Hold fire. If the only thing remaining are light fighters, then I want them to conserve ammo by not shooting and missing them. But if I don't choose this priority, then they'll just engage everything else remaining.

I've considered having priority for specific weapons too, but I remembered that missiles already have something of that sort built-in, like they can only target ships or something. Having more fine grained control is nice, but as a bonus.

Turrets would have the same but simpler, but I want to be able to set it for each individual turret. Like maybe I want my Flak to only engage missiles, even though I generally only run it if I also want it to engage multiple target types, but maybe I want it for the aesthetics.
And also maybe I only want my S3 railguns to engage light and medium destroyers, but leave the various frigates to other weapons/ships. I want to be able to set targeting priorities for that and hold fire otherwise. Though this is more important for missiles with much more limited ammo.
Actually, maybe also allow me to set range priority as I call it for turrets, it'll be optional, but maybe I want them to hit closer targets first instead of further targets since I can then kite them. I'm not sure if this is actually a good idea or not but keep it in mind.

Even though turrets should have covered most of it, ships should also get their own targeting/action list. Although I imagine the targeting would be more like an anchor of sorts, like theoretically if there are dreadnaughts, I would set my ships targeting to the enemy dreadnaught, set range to 10km or something and I guess they would stay out of range while their turrets have their own priorities? Or simpler, I want them to escort my ship, or the fleet carrier or something and screen it while their turrets follow their own priorities.
Which brings me to range, I want to be able to give my ship a range of ranges to stay at in relation to their target or anchor. Like S3 railguns are 6km, and the S3 cannons are 4km. So I want ships with those to stay at 4.5-6km. Because I'm assuming you'll get a bunch of undesirable behavior if you leash them to a specific range too tightly, so as long as they stay in a range I want, it's all good.

And of course the capability to save a list of tactics, so I can easily copy paste towards other ships. And maybe a button to apply the tactic to all ships of a specific class. Actually, also let me do that with loadouts too, maybe I have a whole bunch of fighters with basically random loadouts, but late game I want to standardize, like carriers are coming, I assume then we'll have a lot of fighters too, so this would also ease management.
Bonus, also let me export/import out of the game so we can share tactics we think works.

And another thing, obviously we should also start with a couple simple preset tactics. Like fighters would have anti-fighter, anti-bomber tactics to start with, for those who don't care to maximize it. Ship turrets seem to generally work so that's fine, but the ships themselves could have tactics like brawling or kiting, which I guess is like the current close/long range thing.