After going from level 13 to 14 on the first couple sections of the mountain path in the fjords, I cleared out the group and the next 3 that patrol in pairs, bringing me up to level 15. I had planned to leave then, but decided to try out Explosive Arrows; the damage wasn't usually a great deal more than regular arrows (at least on those opponents, and excluding the area effect), but it is still a fun attack to use. The 3 opponents left on that path and the first two on the beach across the water brought me up to level 16.

I visited Lovis again, and I'm not sure if it was my level or just luck, but got a level 6 mage head on my third reload of the chest by the throne (I took the first loot I got for the other chests there). After entering the Temple of Doom my creature still wasn't any help, but if I was paying attention the skeletons were not too much of a threat. However, if you were to stand on the raft checking the bodies for loot, let a skeleton shoot you a couple times and then jumped backwards at slightly the wrong angle so you hit the railing, slid off and fell in the water, you would die... you know, hypothetically speaking.
In the first encounter with Jagon, a single explosive arrow got rid of him. In the next, I had him almost finished off, with a reasonable amount of health left (despite a couple mistimed attacks and sidesteps), but he got a critical hit in. After reloading I hit him with an explosive arrow, stun arrow, poison arrow and then normal arrows, and he went down quickly (even though the stun arrow didn't work).

I had to destroy a (random) book and a couple food items in order to loot the chest in the cart near the end of that area. Being above level 15 now, though, I tried on each of the sets included with the North American Xbox release. The mining guild bow might be better than my current Ranger's Rest with a change of enchantment; the other sets I'll sell, and sort out the rest the next time I play.