Right now dungeons show up on the world map as a stone archway, with a few variants: Lock: unpurchased treasure hunt Eyes: never completed Empty: completed, but not today Hourglass: completed today But now we can replay exhausted dungeons as many times per day as we want, so having a big hourglass covering the icon doesn't make sense. My suggestions: Lock: fine as is Closed Gate: never completed Eyes: completed, but not today Empty: completed today Also, I don't like having that big blank spot on my map where the level 1 dungeons used to be, so maybe we could bring back the old rubble icon for those? And if you click on them, Gary pops up and says something like: "Thanks to you, there are no enemies for miles around Ommlet!"
The blank spot does mess with me. It's always visible from the Keep, so you'll always see "something's missing." And I think your distinction about eyes in the adventure "doorway" is a good idea.