Yes, the Trader needs more work.
All you need from the Haldor the Trader is the Meningjord (belt), the Dverger Circlet (headlamp), the fishing rod + bait and 5x Ymir flesh in order to craft Frostner.
Those items are very useful, but after that, there is really little need to visit him at all. In fact, I have tons and tons of 'treasure' that is practically worthless, but I keep it all, just in case the Trader gets a larger stock of more items for trade as the game develops.

However, that doesn't mean the game is lacking since there is plenty more for you to do and you're not even half way through the current content if you're still in the bronze age.
You are going to have to find many crypts because the need for iron is almost never ending, even in the current end game, so you'll always need to go back and haul more iron out of the swamps even though you're wearing the top end gears. That of course means you'll be sailing in one of several longships you'll have built by then and nothing in the swamp will be of any bother to you either, so it really won't be much of a chore ;)