I dislike sailing in Valheim for a number of reasons. But one of the main reasons is because even after I build the dopest dock in all of Valheim, my boat will sit there and continue to take damage from the waves/tides pushing it against the dock structure until it breaks and I lose my materials. The alternative of destroying my boat every time I reach land is also annoying, but at least I can keep my materials. I also don't like how the boat can drift away over time.
I wish we had a feature where we could use our hammer and use iron and linen (or maybe some other unreleased strong fibrous material that we create at a crafting station, or just use iron chains) to create mooring where I can tie up my boat. And as long as it's tied up, it shouldn't take environmental damage from constantly hitting the sides of my dock structure. However, it should continue to remain vulnerable to attacks from mobs, players, and collisions with other boats.
An anchor is fairly self-explanatory, but I like the idea of parking a boat somewhere that may not have mooring and you want to keep the boat from drifting away.
Source: https://www.reddit.com/r/valheim/comments/17toeei/feature_request_mooring_and_anchors/