Perhaps the portal could require a little bit of every type of metal to be built (imagining an elaborate, metallic, almost dwarven-like portal design), so that way you can't teleport around placing the portals all over the map willy nilly, it would still be time consuming as you'd have to sail to place them.
I totally understand not being able to teleport metal, forcing the player to engage in the sea exploration (which i do love, even if the wind goes against me every time lol) but at a certain point in the late game, when the bosses have been slain and your viking has chosen to remain in Valheim for eternity out of sheer entertainment, I think it should be possible to move metal around more easily so that viking can construct his Halls in a much less obnoxious way.
If this already exists as a mod, i'm sorry lol i haven't used mods yet. Been playing off and on since release and have about 600 hours in this game and i always get burnt out after the bosses are down and it's time to just build a ton. I think this would help ease that burnout.
Source: https://www.reddit.com/r/valheim/comments/wtln2a/suggestion_dragon_tears_could_be_used_to_craft/
