The system where you do extra damage to enemies lower level and take less damage from enemies of a lower level (and the opposite for enemies at a higher level) makes for a strange difficulty curve.
The game is pretty hard between levels 7-10.
Orobas Fjords has a ton of enemies, but you gain experience so fast that soon there's not much which can threaten you. At level 21, walking from Champion Harbour to the fork in the road gives you an entire level, and clearing out the rest of the road, from High Hall to the Mine gives you just about two more levels.
The Flying Fortresses are also a problem because there are 4 of them, they have enemies between levels 26-29, and doing just one of them should get you from 26 to 28 or 29, making the remaining fortresses too easy.
