I also want it to be able to be toggled between three modes just by pressing a button.
1. OFF
2. Mini mode (shows up at the corner of the screen for easy reference)
3. Large Mode (covers the whole screen so players can get a good look at the world/ dungeon)
The map I would refer to would have to be from FINAL FANTASY 7-9.

Some BLIPS here and there to show your place and destination would be awesome too!
And if your feeling extra energetic, an ability to restrict the map in certain places until you find a map (like in Zelda) would be pretty sweet too.