Starship Building Notes (5e space fantasy)

I've been running my Dark Mana space fantasy setting using the 5th edition fantasy rules for some time now, adding in blaster weapons from the classic Star Wars rpg (the one based on 3rd edition rules).

So, while the personal character stuff all works out, I never had a chance to do anything with space combat or the like. But I've always had some ideas in mind for how I want to help build starships. They would basically be a "Creature" build, like from a bestiary., but have some significant changes and building styles:

ARMOR CLASS

The starship's AC would be equal to 10 + the total bonus of the pilot's "Space Vehicles Proficiency" (which works under "Tools"). So, a 1st-level pilot (+2 PB) with a Dexterity of 14 (+2 modifier), would provide the starship with AC 14.

Adding armor plating to the ship is possible. Light Armor provides +2 AC, Medium Armor provides +4 AC, and Heavy Armor provides +6 AC.

Obviously, during combat, a pilot can use the Dodge Action to perform "evasive maneuvers" thus making  enemies attack with Disadvantage.

HIT POINTS

Similar to Bestiary builds, the size of the HD is based on the size of the starship. However, the base number of HD rolled is ALSO based on size of starship...

Tiny (most smaller starfighters, like TIE fighters): 1d4 HD (3d4 @ Tier 1)

Small (most starfighters): 2d6 HD (4d6 @ Tier 1)

Medium (most transport-class vessels; your basic "Millennium Falcon"): 4d8 HD (6d8 @ Tier 1)

Large (larger transports, such as the "blockade runners"): 6d10 HD (8d10 @ Tier 1)

Huge (capital starships, like the Star Destroyers): 8d12 HD, plus Damage Threshold (10d12 @ Tier 1)

Gargantuan (BIG Capital ships, like Super Star Destroyers): 10d20 HD, plus Damage Threshold (12d20 @ Tier 1)

Additionally, a starship may earn additional HD based on the level of the ship's captain and/or crew's Proficiency Bonus, providing 5 Tiers of Starships.

Tier 1: +2 PB

Tier 2: +3 PB

Tier 3: +4 PB

Tier 4: +5 PB

Tier 5: +6 PB

Each Tier provides the starship with 2 HD (noted above). So yeah, it's easier to shoot down the Imperial Flag Ship when a basic "Captain" is in charge (as he's only a Challenge 3 "Senior Officer" NPC, thus making the ship "Tier 1"), than it is when a Grand Admiral is on board and in command (Challenge 20, Tier 5).

Ships are only "disabled" when reduced to 0 HP, not destroyed. This can be altered for NPC ships, of course. (pew pew pew... BOOM!) This way, people can engage in boarding actions, should they choose, after disabling a ship.

SHIELDS

Most starships have shields, which will be 100 temporary Hit Points. This way, when shields are at 100%, they are fine. But if they've taken 52 points of damage, suddenly the shields are only at 48% strength. Easy to read and use in a game situation.

Shields can be repaired and regenerated by spending an Action to heal them with the Ship's Hit Dice. These are, of course, a limit resource that are only restored with a long rest (and requiring a "repair bay" or something similar).

WEAPONS

I've been thinking about weapon batteries and how they function. 

Obviously, the Ranged Attack Bonus of the weapon is based on the Dex and PB of the gunner.

The basic laser battery is a single laser cannon = 1d6 radiant damage. Remember to add the Dexterity modifier of the gunner.

Upgrades to the Laser cannon is a matter of adding "key words" to the weapons:

Dual = 2x the normal damage dice

Quad = 4x the normal damage dice

Heavy = Increases the damage dice from d6 to d8

Turbo = Requires "Heavy"; increases the damage dice from d8 to d10.

So, imagine the average Imperial starfighter with its Dual Laser Battery, thus dealing 2d6 radiant damage (+ the Dex modifier of the pilot/gunner)

This is about average of what one will find in the galaxy. Most starships and starfighters will be equipped with single or dual-laser batteries. One isn't likely to find heavier firepower except on "air superiority" fighters or custom space transports.

For example of custom space transports, you have the Millenium Falcon's turrets... these are both "Heavy Quad Laser Cannons" dealing 4d8 damage! Woah!

But then, you have the terrifying Star Destroyer Quad Heavy Turbo Laser Batteries... 4d10 damage! Yikes!

Then, when it comes to something like "Torpedos" or "Missiles" those are going to basically be based on fireballs (8d6). 

As an additional note, most vehicle weapons like this will do significantly more damage to non-vehicle targets (like... people!). The blasts would likely also be loud and extremely concussive/explosive on that scale. So a weapon used to target non-vehicle creatures will be dealing additional damage, PLUS a some additional thunder damage, based on the concussive/explosive force. Maybe upscaled, based on the number of size rank differences between the ship and target... I'm obviously still working on this.

MOVEMENT

Most starships start with a Hex-grid movement of 6, to simulate standard move actions in combat. People can upgrade their ship's movement with engine upgrades.

In my larger galactic map, which also uses hexes, a ship can venture up to 6 hexes of distance in a day on standard engine power. Those with upgraded engines obviously go faster.

So yeah, this is what I have for my starship notes so far. I'm hoping to expand on this. Feel free to make comments or make suggestions for ideas you might have to help.