If you don't like the boss fights and don't want to cheat, its probably not a good game for you.

The boss design is pretty good though:
- it forces you to explore a lot more than you otherwise would
- it offers a challenging fight and something to look forward to when the normal enemy have become a bit stale/routine in an area
- the progression locks are pretty soft. You can manage with only 2 of the boss items (you need mountain and plains) if you are willing to work around it. I highly recommend the key to the swamp, but its not strictly necessary.