So once again, I got a bit bored of my current fleet. so I sold them all to try make 1 immortal, yet simple ship that could utterly destroy any puny enemy it came across.
So after a bit of trial and Error, and a load of testing, I present to you THE BOX OF DEATH:


It has 80 MISSILE LAUNCHERS, protected 360 degrees by a wall of 96 SHIELDS
This means no Ship can sneak up on it, as they will be met with a storm of missiles that will immediately obliterate them. the missile factories are placed directly next to the Launchers, giving it a pretty good reload time (Not that any ship below Vanguard survives the initial Volley of 240 Missiles)
Anyway, I've found this ship really effective at taking out all sorts of enemies, the only issue is that its thrusters aren't the best for controlling its speed, so on Vanguard ships they can occasionally crash into it and do some heavy damage.
Saying that, this is a solo ship, so I'd say its pretty successful that it can destroy any ship in the game alone.

Edit: I found adding a sensor, crew and some more reactors to the centre area massively helps this thing. With these additions and a bit of manoeuvring, it wipes the floor with even Vanguard Ships
This is my Cosmetics Version of a Mk2 (It has 4 Sensors just for symmetry)

I've found that upon approaching the enemy head-on, the back side of the craft doesn't fire, as there's no sight to the enemy from that side. This means you can do extra damage by telling the ship to turn slightly, putting the enemy in range, which will then unleash 60 Rockets at the weakened enemy