I have figured out that there are definite visual cues for the things you see on the maps, but I’ve only decoded some of them. The green wispy gas on greenhouses means something is growing in them, the same green wispy gas on fortresses means someone is fighting in it, and the multicolored orbits around an Inn means Dark Detectors are equipped.
I haven’t figured out what the tall golden columns on the Traces means. Something to do with whether I have that foundable in the registry? But I have encountered traces without the gold column that had a foundable (or foundable fragment) that I still needed. Anyone else figure that one out yet?