Anyway I think I am better off making 500 badly made 1k drones and then ordering them to go where I want them to be rather than using a badly made 500k ship
For the sake of maximized power efficiency, 50 well made 10K drones would be your best bet, as that's around the biggest size you can get away with without using too much space for reactors/aux power.
But for a 500K ship, I pretty much agree with
MrFURB on defense, but also on the fact it's not the raw DPS, it's which setup it is on, and which approach to a fight do you prefer. Obviously, if you're a close quarters guy, beam/cannon and cannon/cannon is your friend.
Cannon has a good hit detection and better range than beam, but requires you to lead your shots - if your server has greatly increased sector sizes and your enemy tries to keep at range, that might prove to be a problem even for a 500K mass range ship. However, if you close the distance, wapid fire cannons can shred an enemy with good efficiency.
Beam is easier to aim but has problem with long-range hit detection and hit detection across sector borders or between main and docked entities. Docked armor, especially with defensive effects, makes beam-based weapons drop off in efficiency, and you'll never be able to deliver your full DPS unless you almost ram your ship into the enemy's. Lag makes this even worse (and capital combat causes quite a lot of it) However, if the stars align just right, and you have the right setups, you can deal a lot of damage with them. I personally recommend 4-5 beam/beam/ion setups to strip the enemy of their shielding. Due to beam slave's increased range and high alpha, you don't ened a lot of blocks to deal a lot of burst, and having 4-5 of these on your ship means you can fire one every couple seconds, giving you a good versatility and preventing overkill.
My usual tactic is not having to rely on a single weapon setup; simply because you can't expect to know your enemy. A pure beam setup will perform extremely poor against an armor tank with defensive effects, a pure cannon setup will fail against a mobile enemy that can keep a distance and make leading your shots extremely hard, and a pure missile setup will fail against an ioned up shield tank with some docked spaced armor and a decent point defense grid, due to them being able to kick the shield recharge in between 2 volleys of missiles.
In addition, the weapon setups can be classified by multiple attributes.
Alpha-DPS
Shield removal-armor removal-sysblock removal
Depending on what you want from your guns, you need to take different approaches. For example, Explosive effect on a grid of outputs of a Beam/Cannon is great for block removal but it really sucks as long as the enemy still has armor remaining.
Cannon/punch shreds armor well, but once armor is gone, the projectiles might just go through the ship and lose the remaining damage potential.
Beam/Beam performs excellent against shields if you use ion effect and single outputs, or against unarmored blocks with Explosive and multiple outputs.
Missile/cannon can be great for block removal, but falls off against shields and heavy armor, and requires you to get close to actually land your shots. Can be used to gut a ship once you puched through the shields and layers of armor, provided you can ram a few missiles down the hole you cracked open.
Missile/Beam used to be the jack of all trades and still is huge in capital ship combat. Current longest ranged weapon in the game (with full Beam support) and delivers great alpha damage against both shields, armor and systems due to Piercing or Punch effect not causing damage penalty on shields. The fact that Beam slave missiles also are the fastest missiles, helps against enemy anti-missile turrets. These kinds of guided missiles are best used on large missile turrets (like on Vaygr's feared Despoiler) to abuse AI getting an instant lock on the target opposed to the player's lock-on timer, and don't require you to turn your entire ship to face the enemy. Best paired with multiple beam/beam setups to keep the enemy under fire between missile volleys and not let them recharge their shields, while still keeping at range to make returning fire more difficult. Also, using small missile/cannon or few block missile/beam setups set to the same range will help to occupy enemy point defense and ensure your payload is delivered.
So, 4.5 million DPS can be more than enough, and can be way too little, it all hangs on what weapon setups you put it into.