I made a suggestion to modify the Scribes Profession allowing us to create books for guides for dungeons, a guide for monsters giving the ability to draw (tablet pleasure detection), but also suggest maps can only be produced by players. More can be found here:
Map Maker, Artists, Public Performance, Guides in-Game.
Now I bring another suggestion in which people were talking about guilds or people fighting over dungeons and such and I thought, wouldn't it be great if we could cast an illusion spell to hide the dungeon entrance? Of course, detect magic and dispel magic could come into play to find it, but this could give an advantage as well allowing a guild to prepare themselves, aka, find their way to the dungeon and etc.
I thought this kind of feature would be also immersive and not only PVP but adding secret paths in dungeons with illusion spells could be amazing. I'd love to explore dungeons with such things, of course, this would be great for map sellers, more variety depending on what they can do.