Right off the bat there is an area filled with super high level monsters and is accessible by the player and if you go along with the story line there is more high level monsters you have to fight when your only level 3
No matter how awesome a game is even Final Fantasy III can be killed by game mechanics. In this case it is with how the saving worked. The game designers were so kind to make an area with difficult monsters easily accessible early on (before I could figure out how to save). I accidentally got killed in such a battle early on and initially was like oh well looks like I am probably going to get penalized in some way instead it returned to the title screen. Since I had not been able to save I lost all my work. I personally am not big on repeating entire dungeons let alone losing everything.