If Ihad to do this, I would probably write a simple GDL object.
In GDL you can obtain the X and Y coordinates of the point the object was inserted. Here is a page that writes about this. You need the SYMB_POS_X and SYMB_POS_Y variables.
See at
http://www.archicadwiki.com/Global_GDL_Parameters#head-931f5bd5cfdd709420576c31cd1b347f7925328c
The 2D Script of the object would probably be just a crosshair and a text. I would display the User ID of the object in that Text for two reasons:
1. It can be listed/scheduled
2. When placing these successive object representing the points, the program can be set in Preferences to automatically increase the User ID. Or later, with the Element ID Manager, the IDs can be rearranged.
Then I would create a simple Interactive Schedule that would list these objects, their User IDs, plus their X and Y coordinates.
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