Here is me and a friend's "traditional" brig setup for SotD. We typically are solo engaging (1 person on the ship), or we'll bring a brig and a schooner (1 person per ship).
Brig with 12 gunports, 12 cannons. No extra deck or rear cannons
No extra pseudo-armor (wood ceilings/walls)
3 Large handling sails
Helps with wind angles in combat
Great acceleration/deceleration capabilities (you can dodge volley's by "tricking" them into firing where you won't be)
If sails are low (like 5-20%) your ship will turn much faster
Pre-combat inventory check (minimums):
400-1000 cannonballs (ammo box)
2000 wood (resource chest)
5000 fiber (resource chest)
3000 thatch (resource chest)
300 metal (resource chest)
100 hides (resource chest)
5+ replacement gunports
5+ replacement planks
1 replacement sail
1 replacement wheel
1 replacement deck
1+ repair hammers
1+ grappling hooks (for loot, and anti-mermaid if fighting in power island grid)
1+ spyglass (so you can see level's & hp at distance)
1+ sextant (mini-map, gps, speed HUD)
* replacement ceilings/roofs/walls
* Highly recommend you put a small storage chest somewhere in your central area or pilot house (easy to get to from wheel) that has all of your emergency gear above in it. Paint it red. You DO NOT want to be hunting for any of these items during combat.
Prioritize leveling up Resistance first and then Damage. The more resistance you have, the less punishing it is to not avoid a incoming volley. SotD galleons are the exception here, even with high resistance it is still possible to get a tight spread and get planked in one volley. Early on, before you have much resistance, you will be taking a lot more damage and dealing with missing planks.
Mind the wind, know your turn before you do it. Use changing angles and speeds to both get into targeting position, but to also fake-out & dodge their volley's. Use either "free fire" or "fire on my target" with NPC's. Once you have high resistance, high damage, and blueprint cannon's/planks; you'll be more into a position to face-tank most everything except a galleon.
Big incoming damage, "your sinking!", and missing planks
First, do not panic! Unless you really messed up and have 3++ missing planks, you have a couple of minutes to deal with the situation (even in the worst case, you still have some time, just have to be fast). You are not in immediate danger of losing your ship.
First, point your ship in a good direction with good wind. Set your sails to full and leave the wheel to deal with repairs. Yes, you will still be taking some incoming cannon fire, but you will quickly be out of their range.
Second, repair (with hammer) any planks with leaking status as they are about to be destroyed. You can repair the same plank multiple times in a row to get it to repair faster than just the slow repair over time. Ignore missing planks until you fix the leaks (you can't do anything with them yet anyways due to "debris smoke").
Third, replace missing gunports & planks once smoke has cleared. Repair them immediately as well. (Pro-tip, switch away or unequip plank from hotbar quickly. You do not want to be accidentally replacing random good planks with accidental clicks)
Fourth, pop your head on deck and see if you are out of aggro range, if so, drop your sails (either from wheel or use whistle menu from anywhere on ship).
Fifth, repair anything that has more than 1000 points of damage (ignore slightly damaged stuff, waste of repair materials). Do not forget to check your sails, they take a lot of damage!
Sixth, turn around and get back to sinking that SotD
Rinse & repeat, keep an eye on your repair materials and work your way up through tundra, polar, and powerstone grid SotD.