Marking on the Map

I wish we could mark on the map as if we were to mask it behind a glass screen or use a projector to put the map on a whiteboard. It would be cool if the game provided a few icons for us to put on our strategy map to remember stuff we had in mind. I was thinking of:

• arrows
• tiny flags (multiple colours)
• hammers (to signify building)
• crossed swords
• shields
• eyes (single eye icon)

We should be able to place more than one of each icon on the map, and for the arrows, crossed swords and the flags, we should be able to pick colours. For each icon/marking we should be able to add/view notes and select whether or not we want our allies (persons with shared maps) to see it.
On the entire map itself, we should be able to toggle our strategy markings, and strategy markings of our allies and whoever we get spy reports on. We could choose, from the diplomacy panel, whose maps to see or not (of course we can't see icons on maps that aren't shared with us, or maps we have no intel on).
It would be a great feature for personal and allied planning. I tend to set regional capitals, and I would love to have a flag to signify that, but different players may find different uses for each icon.