PVP, isn't about hull or defense. if the only thing you have is hull or defense, then you are turtling.
Obviously you should piriotize attack first. But then the question is hull or defense?
Hull is great because it takes less space than defense, and it does the same thing as defense; allows you to last longer in a battle, which is great.
If you are a low rank, then you won't be able to build 5 hull module without making yourself weak however if you are rank 200+ you can build 5 hull module without dying.
So hull is more important than defense but balance is still very important.
i am rank 264, i got 5 hull module, 8 attack weapon and 2 defense module.
Admittedly i could balance my modules better. But i don't have any money at the moment.

TL;DR hull over defense but you have to balance it.

I'm not much into PvP. If someone is offlline there's no challenge. I don't worry about my stats either. Mainly focus on killing NPCs but since the battle market I've started doing PvP.

My ship's built primarily for NPC killing but it makes a good PvP design. Obviously max attack is important. I stopped putting rank points into ship size at Massive Levianth. Don't really need much more for NPC hunting. (I'm up to a Heavy Star Destroyer now just from ship bots).

Early on I had high hull and low defence but as ship repapir costs went up I started pushing my defences up after about rank 200. This really helps stop other players attacking. It costs a lot more energy to burn through the hull of a ship with high defences. A lot of players are going through their battle tab looking for easy kills to get badges. They'll think twice about burning loads of energy on a ship which has a higher defence than their attack. This works even better if players can't see your hull size. It stops players randomly attacking you.

Another good defence isn't defence ship parts. It's your stats and reputation. Who would you rather take on: a passive grand master or an insane grand legend? You know the insane player's going to badge you back so if you want to get in a fight then go for them. People with poor stats are ripe targets for farming....except now they've changed the Halycon Trap....

My opinion...

Hull + Defense before weapons. Why, you ask? Upkeep.

I have 8 heavy null rays but can mount 8 heavy thetacron cannons but I don't. If I mount these, that'll add roughly 1.6 billion more upkeep. Each heavy null ray costs 67 million upkeep each while heavy theta's cost 265 million upkeep each. Chaos / NERF guns are much worse. 1 billion upkeep EACH. So thats 8 billion upkeep for weapons if you use NERF guns, while the total upkeep for having every module in the game installed is roughly 18 billion. Thats almost 1/2 of the "ultimate" upkeep for weapons. Thats way too much. So...

8x Heavy null rays = 530 million upkeep total + 2400 attack
8x heavy thetas = 2.1 billion upkeep total + 2864 attack
8x NERF guns = 8.2 billion upkeep total + 3416 attack

If I spent roughly 500 rank points into tactical officers, I'll get about 1000 attack. That means I can keep my 8x Heavy Null Rays and have equal attack power to 8x NERF guns for about 15% the upkeep cost! Thats a HUGE amount of money saved.

Hulls and defenses cost nowhere near as much as weapons, especially in upkeep.

First, shout out to Tommy. Very nice slow ranking sir.
Second, I preached Hull & Defense in AU.
If you want to pvp and be a strong killer with few deaths,
then defense beats offense in terms of your research planning.
If you want to npc more, then go all offense.

Bluecifer and ExSeaD, precisely my point.. good for you.

In the early levels when repairing is cheap... Definitely go hulls. As you start climbing above 200 - 250 level, defense starts to become much more crucial as a lot of ships have higher attack and repairs start becoming much more costly. As repairing becomes quite expensive, ~lvl 350, then shields start looking pretty good to keep those repair costs down while NPC-ing, etc.

Hull times defense is what matters. Then it depends on the % boost from some number of decks, from either source.

for dozens of ranks now i have been at the repair cost cap of 200 million

the way i see it when you are around my rank (now 355) it is best to get hull research completed (i have neglected my hull since i was under rank 200, been at Deep Core Neutronium since then), well even if much lower than my rank, cuz if you can complete hull research and you have the credits to pay the 200 million it is all a bonus the farther past that cap you can get (that is still paying 200 million for much more hull points) say you hit the cap at around 8k hull and if you can get 12k hull or more repaired for that same cost -BadaBing- 50% bonus for the cost, and the more Durtanium Brackets you get the bigger that bonus

just a thought and kinda scattered thought at that

yep the more npcs you kill or pvp you do the more you save. I'm still a ways off from the 200 million repair cap but will get there soon I'm sure.