Hi!
How effective is the Most Defense strategy?
In early to mid game it's simply a killer strategy. What I need for it to start working is:
- medium hull,
- 10-15 spaces for weapon(s) - any type my opponent doesn't use defenses for. Attack strenght 2-4.
- 10-15 spaces for engines (Ion or Impulse III). If small uni or lack of space on ship, then even none,
- in remaining space I fill the proper type of defenses for the weapon my opponet uses. Defenses are usually strenght 2-3 each, 6-8 pieces on a ship.
Such a ship usually destroys 3-6 fleets of opponents's ships (usually 3-4 small or medium ships), before I need to recall it for repairs. I also build only a few of them, depending on the amount of fleets I need to destroy to successfully invade and conquer most AI's planets in the shortest time possible, to avoid the hattered "seecret meeting - war has expanded" event. In game size I like to play (5-10 planets per player) 3-5 such ships and a dozen of troop transports effectively remove one AI from the game in less than 5 turns. After one AI is removed, I IMMEDIATELY move those ships on the next AI that's using the kind of weapon my ships are properly defended, and repeat the previous procedure. And keep repeating until there's no more AIs that can be conquered so easily. At the mid game I have usually removed 2 or 3 AIs out of 9, and taken their planets. The rest of the game is then just a matter of execution.
Like I mentioned, such a strategy works perfectly in small games I prefer to play for two reasons: I dislike managing huge amounts of planets, and my weak home comp also.

I also see a mayor weakness in such a strategy: weak-attack ships are way to easy counter-designed. But in ALL my games I haven't seen a good counterdesign. IMO this is either:
- I remove the AI to fast for it to react, or
- AI doesn't recognize my low-attack ships as a threat, and keeps building wrong ships.
IMO both reasons could be tested in a game with less opponents, but the same amount of planets, so ~20 planets per player. Maybe I'll start such game when I finish my current one, just to check what will happen.
BR, Iztok
I've tried out this strategy for the first time in my custom race game with the 'Nuts' - A Good-Aligned Super Dominator anti-Snathi squirrel race. With Fast tech rate, I managed to get your described kind of ship by the beginning of 2227. I built one, and sent it to destroy the technologically lagging Drengin.
The Drengin Defenders had one Stinger and one ECM - but being in orbit, their attack was doubled. So the net result is that they had 4 Missile attack and 1 Point Defense each.
My medium hull had an Impulse Drive Mk.3 engine, 3 Missile attack(it was armed with a single Harpoon), and 23 Point Defense, which comes from six Good-only Telepathic Defenses combined with a 10% Defense Bonus from the Universalists Party, a 5% Weapons/Defense boost from a Military Resource, and another 5% Defense Bonus from researching Telepathic Defense.
I also had a 50% Luck Bonus.
So during an attack on Kona, my cruiser destroyed all the Drengin Defenders but one of them managed to inflict 3 damage AFTER the killing shot had hit it. During a later attack on Drengi, the exact same thing happened. This time, I got a screen of it.

Such illogical-looking damage never occurred again in the game. The Korath later attacked me and paid for it with the total destruction of their empire by my improved defensive ships(re-optimized to fight MK.4 Railguns with Arnorian Battle Armor and Photonic Torpedoes, and powered by a Warp Drive engine).

Recently, I launched a surprise attack on the Korx, who had Harpoon-armed, ECM-fitted Frigates with Orbital Fleet Managers, better Logistics(Advanced vs. my Enhanced), and an economy slightly stronger than my own. I managed to destroy the Korx with frigates that were fitted with Photon Torpedoes, Mk.3 Droid Sentries, and Warp Drive Mk.5 engines. Never did my 3 frigates(that's all I ever built) take any damage again from ships, only a bit here and there from beam-armed Starbases.

But what happened in the first scenario? Is this 'defense depletion', or a bug? I know my defenses couldn't have rolled 0 or 1 - with 50% Luck, they should've rolled at least 11.
" But in ALL my games I haven't seen a good counterdesign. IMO this is either:
- I remove the AI to fast for it to react, or
- AI doesn't recognize my low-attack ships as a threat, and keeps building wrong ships."
This game was Challenging with all Bright AI, large Galaxy, Rare Stars/Planets/Habitable, and Abundant Asteroids(My ships are mostly built from asteroid resources). The Drengin and Korath were removed too fast. The Korx did counterdesign(hence the ECM), but couldn't research past ECM 3 before getting destroyed.