@BattleCruiserCommander Normally, I disdain playing with/against illegal ships, as it's too easy to make a bank of ridiculously large rails and penetrate any legal-practical defense, but since Sempai summoned me...
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So the Overlord-class is very aesthetically pleasing... But testing it has revealed a multitude of deadly flaws, especially against opponents of similar cost-tier. (Note I gave you a handicap of 1m, deploying a 5m for the first test, and that this version of the ship is still very much a WIP and requires further refinement)
The Overlord's spinal weapons are not at all adequately protected. The very first exchange alone had two of your railguns immediately get taken out, and I wasn't even manually piloting/railfanning...
Your logistics is inadequate; the supply sources (energy & ammo) are located very far from the systems that need supply; especially your PD and Railguns. After the initial free two shot burst, your rails fired once for every four of my salvos.
Partially due to lack of engine rooms, your power/weight ratios are vastly insufficient for a ship of it's tonnage.
No offense intended, @Equalizer or I could use 2x 1.5m to take out the Overlord; your ship is extremely unprotected against the weight of fire a ship of the same cost tier can hand out, it's slow, unagile, with poor turning characteristics, and has awful sustainability in a fight due to it's long supply chain.
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My advice: All the top tier players other than @SpaceCat use highly compartmentalized builds; and Luke doesn't make 5m+ supercapitals. Compartmentalizing lets you more easily optimize specific groups of systems, leading to a more optimized overall design when you build them out of optimized parts, and lets you build a big ship much faster than by hand.
The logistical throughput and latency available in Cosmoteer - crew hand carrying stuff - is too low for centralized designs, feeding from centralized factories and reactors across the ships, to compete with compartmentalized designs.
Add in the additional volume wasted from fitting in huge amounts of moving walkways, and you can see why (almost) all the high tier players have built their ships in 1-reactor chunks, usually with the factories directly touching what they need to supply.