As it stands now, there is absolutely no reason (other than roleplaying) to build large or huge ships. They are beyond bad in comparison to the other hull sizes. Let's take a look:
Your starter warships and extremely useful for stacking weapon amplifiers and other fleet bonus modules. This seems to be the current "meta" of the game.
Just spam a whole lot of them, set them to support role and bunch them together with a couple of Small or Medium hulls (as main weapon carriers) and you get something like this:
More module slots and hitpoints than Tiny and may also take over the swarm role described above. Also, they are great for armed standard roles like survey ship, explorer etc. in the early game (needed due to the pirate, space monster and sentinel spam).
Your standard weapon platform. Enough module slots (12 with maxed miniaturization) for any task and lots of hitpoints, all for the cost of 4 logistics. Overall just great bang for the buck.
15 slots for 8 logistics = 25% more slots *cough* than Medium for double the logistics requirement. Excuse me?
22 slots for 16 logistics = 83% more slots than Medium for 400% the logistics requirement. Why should anyone ever build those?
IMO, both of these should be buffed dramatically, since right now they are light years away from being a viable alternative to any of the other hull sizes, despite being endgame techs. My suggestions:
- increase module slots from 15 to 24 (assuming maxed miniaturization)
- give them bonus: ignores 75% of damage received from Tiny, Small or Cargo hulls ("light unit killer")
- increase module slots from 22 to 48 (yes, why not)
- give them bonus: ignores 75% of damage received from Medium or Cargo hulls ("cruiser killer")
This way, both of these hulls would be useful again and fit their position in the tech tree. And they would still be far from overpowered - due to the low numbers of them in any fleet and the GC targeting system.
Some other issues that should be addressed:
Instruct the AI to always use the +20% weapon amplifiers on their ships (for Tiny, Small and Medium at least). Right now it's trivial for the player to outdamage them on any difficulty level (see pic above). Unfortunately, this probably requires a rework of many many core designs.
The whole one-per-ship module system is a mess. At the moment I can put only two carrier modules on a ship, no matter its hull. So you don't want me to build a Huge hull supercarrier filled with carrier modules, but at the same time you have no problem with me creating a Small hull with 2 carrier modules and throwing 40 of these ships into a fleet? Doesn't make sense to me at all.
Same problem with many other modules. IMO, the only modules restricted to one-per-ship should be those giving fleet-wide bonuses and the special ones (colony, constructor etc.).
Cargo hulls should also be given some love. Right now, they give 6 slots (one less than Small hulls, with maxed miniaturization) and 20 base hitpoints. I don't see their usefulness beyond the very early game. My suggestion would be to go back to the GC3 route and give them 10 slots and a base hp of 1 (which can be increased by hp modules if desired). Maybe some special modules (e. g. transport, constructor) should be restricted to Cargo hulls.