Map markup tips?

I love being able to mark up the map any way I want, but the game doesn't offer the icons that would make the most sense to me personally. (For example, a lock icon for locked doors, a treasure icon for where there's always a treasure chest, a gear icon for a dismantle station, etc.)

Sure, after a while I learn where everything is by heart, but on a large map like Farm Town I still get lost sometimes.

What symbols do you all use to mark stuff?

(I use a white dog bone to mark buried treasure, a green crosshair to mark locked doors, a gold lunch box to mark loot chests, a green bullseye to mark the dismantle stations, and red crossed swords to mark where the bosses tend to spawn.)