I've not yet killed Eikthyr after 225 game days (like to be thorough, not rushed). But I have upgraded my workbenchs and tools/weapons/gear/etc. to level 3. This expands what you can craft and upgrade quite a bit. At this point my skill levels and weapons make every Meadows and Black Forest enemy that I've run into doable unless I let myself get gangbanged.
It's getting close to Eikthyr battle time though. Meanwhile I've marked bunches of ore locations for copper and tin. My goal is to completely uncover all there is to find on my starter island before I take on Eikthyr......and that island seems kinda BIG. lol