Fleets are still better than single ships though.

3 attacks vs. 1 attack (fleet), vs. 3 x (1 attack vs. 1 attack)

Well, it's more realistic that way in a sense. 10 normal bullets to your bulletproof vest is not the same as a single bullet 10 times the size ramming through the vest.

On the other hand, 2 lasers on a ship IS 2x more powerful than 1 laser on that ship.

And yes, weapon mounts take a little less space on smaller hulls.

You could argue that the combined attack against 1x defense makes sense, in a way.

Overwhelming shield capacitors or something might be the shield version, nanobots or something regenerating armour after the round is over for that, and countermeasure launchers reloading? Or just not having enough launchers to handle all the incoming projectiles.

If any of you have played Battlefleet Gothic (warhammmer 40k fleet battle spinoff kind of thing), that is sort of how it works there, with ships having shields that regenerate at the end each round, and defence turrets that could be overwhelmed by large swarms of bombers.

Then again, for purely practical reasons, it might take up fewer system resources to just abstract it a little and give every ship infinitely regenerating defences, that are fully effective against every one ship attacking. My system is pretty much at the edge of the recommended requirements, with the exception of 256mb of ram, so I'm not complaining if that is indeed the case

I do hope it is possible to overwhelm defences with multiple attacks in the final version, however much my cpu might object to having to do all those extra calculations. *nudges lazy cpu*

Ships fire individually. So three 2-attack fighters versus a 2-defense ship would be calculated as 1d2 vs 1d2, three times.

Actually, most of you are WRONG

well, people with the rank of diplomat or amabassor are gamma testers. So they should know how the battle works.

But reading the various posts, one must be careful about where the combat takes place:
- if you are on the galactic map, ships and fleet are stacked. So only one component of the stack (a ship or a fleet) attack or is attacked .
- if you are looking the combat with the combat viewer, the side that is composed of fleet is detaille by the ships that compose it. And all ships in a side fire before the other side return fire. when doing so, each ship of a fleet fires individually against the same target, until it is destroyed. If the target is destroyed ands some ships may still fire before the other side return fire, they fire at a new target

I hope it is clearer

Actually, most of you are WRONG. Unless the manual changes, here is the way it works

The manual is misleading.

While a fleet of four fighters could indeed attack for 4d4 damage per turn, they still fire one by one for 1d4, with all available defense of the targeted ship brought to bear against each individual roll. This in fact continues on an even smaller level as well. If a ship has multiple attack types (say, both beams and missiles), each attack type is rolled separately against all available defenses of the targeted ship.

For example:
Attacking ships: 2x frigates with 4 beams and 4 shields.
Defending ship: 1x cruiser with 4 missile, 4 beams, and 2 shields.

Attacking frigate A rolls 1d4 beam attack versus defender's 1d2 defense.
Attacking frigate B rolls 1d4 beam attack versus defender's 1d2 defense.

Defending cruiser rolls 1d4 beam attack versus Attacker A's 1d4 defense.
Defending cruiser rolls 1d4 missile attack versus Attacker A's 1d2 defense (shields are not optimal, so sqrt(4)).

Note also that even if a ship has multiple weapon types, it will still only target one enemy per round (normally if you have two ships in your fleet and the first destroys its target, the next will attack a different one). The multiple rolls will however be combined as one line in the battle viewer, but they are resolved internally as two or three different opposed rolls.

Believe me, I've examined the in-game workings of the battle system at length, and discussed the behavior of multiple weapon types on one ship specifically on at least one occasion with GC2's lead developer (Cari).

It's worth noting also that if it worked any other way than as I describe, defenses would be completely and utterly useless once fleets came into play.

Fighters are far from useless, even with the way the battle system is. One of my favorite tactics in the early game (or any time versus a weak enemy/low difficulty AI) is to crank out swarms of the cheapest fighters available (a tiny hull with the earliest available weapon that will fit on it, a range extender, and not much else), and plant military starbases near my objective to greatly amplify the fighters' power. Military starbases can add tremendous amounts to each nearby friendly ship's attack power.

For example, I recall one game where I had two or three fleets of up to eleven of these cheap fighters based at my enemy's border. With a military starbase holding five or so attack bost modules nearby, Each fighter was boosted from having a 1-point attack to having 10+ attack. With a fleet of eleven of them, that meant I could deal out up to 110 damage per combat round. Great for obliterating enemy fighter fleets and poorly defended ships, but they're easily wiped out if they get out of range of their starbase or if the enemy fleets up ships with enough HP to withstand my fighters' attacks (since the fighters go down with one hit).

As you can see, there's quite a bit of depth in what sort of ships you can design, and how effective they will be. Rest assured, it's pretty well balanced so that no particular ship types will ever dominate--your effectiveness is directly based on how well you counter your enemy's weaknesses.

Without getting into attack/defense/HP values, the Dreadnought would obliterate one fighter each round until they're gone, unless the fighters are able to nickel-and-dime the Dreadnought to death (if it has poor defenses or if the fighters have a military starbase nearby to give them the edge).

Of course, if your enemy fields Dreadnoughts, fighters may or may not be your best choice. As said previously, it all depends on what sort of weapons and defenses the enemy puts on his ships, and which ones you have available to put on yours. If he uses lots of defense and you only have the weapon type it directly counters, you're best off going for heavy hitters. If it has poor or no defenses, fighters would be a viable option. Or, depending on how heavily the game weighs each stat in the targeting algorithm, a mixed fleet may be the best choice.

Ships fire individually UNLESS combined in a fleet. In that case, their attack value is combined against a SINGLE target (each round of course).

Well, it should be understood the following way:
On the galactic map, the ships engage combat separately UNLESS combined in a fleet. In that case, during the combat, they concentrate their fire on a single target.

Area-effect modules on starbases (i.e., most non-mining, non-starbase-only modules) give benefits within a fixed radius around the starbase (I believe it is 9 or 10 tiles on the map).

Starbases indeed to have an 8 parsec range.. I counted. (turn the grid on!) That's something you also need to take into account when setting up your economy base infrastructure with production boosting modules.... you want to get as many starbases overlapping the same area so placement is key!

dreadnought can attack all ships in a single turn or to attack all 3 corvettes will have to wait 3 different attack turns?

The dreadnought can only fire on one corvette per turn, so even if it can kill a corvette in one shot, it will still take at least three turns.