I have suggested this some time ago, and i still think this would be a easily implemented feature that saves some time.
When marking GCPs or MTPs, make a button toggle that when enabled hides pictures that are manually marked.
This way once the point is marked in a picture it is hidden and the next one takes its place, allowing for much faster marking with less clicks and mouse movements.
Toggle it back off to show marked pictured for adjusting or similar.
Perhaps add a double click, right click or space click to skip/hide a picture that does not show the point.
Would not take much programming to implement and would be a decent productivity boost when the gcp count goes up.