RIP OP.
Yeah the Karve makes you feel invincible after experiencing the Raft lol

If you are going for long voyages on the Karve, while not recommended, there are some ways to go about it. I still go for more risky voyages in my Karve because im more used to it.

First things first, hug the coastlines of islands and avoid open ocean when and where possible ESPECIALLY at night. However be aware that sailing close to the coast means you will need to keep an eye on 2 major things and they are submerged rocks and Leeches.
The rocks are easily combated by keeping your camera zoomed out as far as possible and look 3/4 top down, way easier to spot them.
The Leeches are where i recommend sailing a bit out into the ocean to avoid the swamp.

I also recommend stopping every few islands in a meadow area and repair your ship and sleep so you lower your risk of running into serpents.
I tend to have a dock on every massive island late game because of this and its super useful.

Tip for fighting serpents: You will see them rear up, roar and shake their head fins. Just as the roar finishes it will charge in a straight line. The trick is to line up your boat so it is facing direcly away from the serpent and just as it finishes roaring, hook your boat left or right.
I've not been hit by a serpent in ages because of this trick..... only my own arrows lol