My idea would be to add true 360 degree photographies. You can easily take them with 360 cameras like the Ricoh Theta V (which has inbuildt gyro information for a straight horizon) or other cameras. This gives a much better idea of the actual location in reality than any photo or simple pano.
If you think that further in regard of documenting field progress you could add photos of the same position at different times to document the actual progress with pictures (timetravel). This could be a handy feature and helps disussing things without the need of actually being at the site as well as for documentation purposes.
I understand that this is not possible at the moment but it would be a great option in future.