I'm 32 now, still in the fjords. I haven't been to broken valley again yet. Will the story bring you there, or do I need to go there on my own? I haven't been to the mine either and as I recall, the enemies are about 27 there ?
I just went there anyway, kiled everything in sight Came across two commanders i needed to kill anyway and everything was very easy, as my level is a bit high for the area
starting at lvl 28, its pretty safe to go there. lvl 30 you should go there. Just save often, the poison fog is pretty high and will get you when you least expect it in broken valley. Once I landed on a perfectly visible platform and started taking damage. Same with Lovis' tower.