Built this in creative mode over an hour or two; it's mainly just a cosmetic ship, but with the amount of guns on this thing I'm fairly sure it can beat anything below Vanguard class ( I tested it on my Vanguard killers but I'm not 100% sure if it can beat them. )

31529.4 Tonnes
2906 Crew
14,144,350 Value
Next up is my first Vanguard Killer, The King Beetle. Built this on my.... 6th playthrough? I hadn't learned proper corridor layouts or designs yet, so it's kinda slow and hasn't got a very high DPS. But the initial volley can wipe out pretty much anything below Vanguard.

3345.9 Tonnes
494 Crew
1,917,000 Value
Then finally is the support ship to the King Beetle, the Scarab. After I got to around veteran/elite level with the Beetle, I decided I wanted to built another ship from the ground up. I love the way mass lasers look so I decided this thing would only be lasers. It had a pretty cool look, with the top bit being this sort of mouth with a hundred teeth sticking out. It's pretty crap honestly for fighting anything with a lot of cannons or lasers, but the idea is you get 2 or 3 of them to swarm something larger with the King Beetle hung back and blew it to pieces with missile spam. Worked pretty well in practice.

739 Tonnes
148 Crew
631,400 Value