Actually the biggest reason this game is tolerable to route.

Maps of dungeons, as well as their variants, where enemies are located (not always where enemies that drop keys are) Arrow pickups, and other useful information, as well as full overworld maps.

It's not perfect but this would be a nightmare to do any kind of routing without this to be honest.

Even if you aren't routing, dungeon maps would be very useful to understand so you are less likely to get lost in an unfamiliar dungeon generation.