As I've said, my goal is to reach Lv40 (at least). Not because I think I need the levels, just for its own sake. And finally I approach.
I counted the EXP from all of the Fjords quests (besides the two skill trainer quests, needed to get wisdom to Lv15, and the runes of wrath, needed to unlock the high hall trader), and it is 292,255 (with Lv15 Wisdom and all optional EXP rewards possible). Leaving all enemy structures (goblin camp stuff and the fortress towers), they will probably be enough EXP to boost me from Lv38 to Lv40, with Lv38 achieved exploiting respawning enemies in Keara's fortress.
The EXP needed from Lv38 to Lv40 is 304,200, leaving 11,945 to be obtained elsewhere. I'm hoping the defensive structures will supply most or all of it!