Notes:
1: This is not met to be hard nose military science fiction. It has elements of Science Fantasy in that one class of said enemies are creatures from another dimension. As in they can be demons, angels, love raftian Gods, straight up ex Gods and so forth.
2: Pulse Drive does not use nuke bombs. It is called pulse due to the ripple/ pulse glow. It's more like a ionic drive, but with more pysg.
3: Blame the die for the D Engine. Which is a nod to Cthulhutech. And honestly if you knew that reference you would know it is a advantage but not that big. As the Imperium spent its time trying to make itself self sufficient from limited resources. Even as far as artificial fuels that regenerate.
4: The Subspace teleporter can only be on Battleship+ sized ships. At cost of space for other things. Teleport is once a fight and maunly there to leap into firing range for the big guns. Or tactical withdrawal. It is from the teleport tech you have. And to make it smalllwr or more uses got to revise the Hell out of it.
5: Since a issue with dust casters change to this.
Spread Cannon: A magnetic rail gun array that fires off basketball sized spheres. Limited range due to spread. But devasting in proper range.
6: All ships move at same speed in map. Not in combat but in map. As it is dependent on technology.
Warp: Slow, no need of hyper lanes
Hyper Drive: Faster but need lanes and stops. So things can happpen at points.
Gate: Instant travel gate to gate.
Jump: Do not have but faster than hyper drive and no lanes. Like super warp. There are balance issues though, not addressed until it's available/plot.
In combat Corvettes are fastest. But can die easily. Bigger ships slower, but harder to kill.
As for ships. As in available
Corvettes: Currently escort ships and heralds. Heralds are beefed up in speed but less gun. Used as messenger ships.
Frigate: Basic patrol boats.
Destroyer: Come in gun mode, bomber (decked to bomb planet) or missile boat (loDed with missiles for space combat)
Should be noted with fabricators your ships do not run out of ao (in combat can happen but when out, the lil guys restock with no need to supply)
Cruisers: Harder to kill. Also the first ship to be customized as it hS eight slots for weapons systems.
Battleship: At cost of four slots of 14 can have teleporter in.
Dreadnought: Bigger battle ship. Can be a carrier, or more focused kill o Atic.
Titans: So big cannot dock on planet. Twenty two custom slots
Leviathan: Defender of Holy Earth. Currently 30 slots. Built to last, and the size of the country of Russia. Fewest ships.
Space Stations: Immobile. But protect planets and repair docked ships and such.
And Molten Guns can now be projectile Guns, first hot projectiles of liquid metal death.
But yeah fartherest ranged weapons are lasers and missiles, projectile is more up close but deadly.
Edit: Yeah at size cruiser ship commanders can pimp it out with selection of weapon lay out or bonus gear. Only bonus gear is improved/pulse engines or teleporter. Cruisers cannot get them but battle ships+ can. Engines is two slots. Weapon systems cost one except macro cannons and molten guns. Which are three.