The exporter of panoramas should have a leveling horizon option. Doing that in 3D view is not accurate at all. We should be able to place a simple line and then using the mouse correct position.
Possibility to export panorama as layers would be great. It will give a full control of the image in postproduction.
Even greater it will be if we have a chance to export those layers as PSB file.
With these upgrades, Metashape will become pano stitching software killer.