lifebuoys

[Clemence]

you equip them when you go venture with your boat, so in case of accident/sinking, you just stay here without being able to move, or very slowly ?

[Headchef]

http://ringofbrodgar.com/wiki/Silver_for_the_Ferryman

This.... or drown

[Clemence]

but why relying to magic when a lifebuoy is so easy to make, as long as you think of equiping it before your trip ...
may need leather, and tar to keep the air in ...
or a safety vest made with conker ?

[Headchef]

Because the current item makes you have to be somewhere in the game, where you have silver and goldbeater skin, and the alternative you present sounds incredibly cheap making water non-dangerous for the entire game.

[havenman]

I was trying to post this idea, it needs
I also want Kraken, Giant squid, Mermaid, Sea Serpent, Mermaid

Devil Fruit, Cannon Battle, Ghost Ship
watermelon + fireworks + palm tree + Coconut juice + Tropical Drink + ice making
suntan system is also important + Sun cream in summer

[FrankMcFuzz]

I don't get it. Why would you want this? Boats don't spontaneously explode.
(EDIT) I forgot about deep ocean. There's a solution to this thought: Don't go in deep ocean with a rowboat.

Swimming across rivers is actually not that dangerous. You can do it with con 10 provided you have full stamina and don't intentionally choose the river's widest point. Once you gain access to things like walrus boots/cape and seal pants, or the fisher and pearl diver credos, water presents absolutely no obstacle even without access to the ferryman ring.

You're asking for yet another item that increases your swimming? I don't get it.

havenman says:
palm trees and coconut juice, suntans are important, other mental nonsense

I'm not even going to address this mental post but I think you're confused of the setting of Haven and Hearth.