I constantly find myself wishing for some simple 3D modeling tools inside of PhotoScan, in order to fix up some glitches in the dense reconstruction.
While I can easily export the mesh and edit it in some 3rd party application and bring that back into PS again, it would be MUCH better and faster if I could do the modeling while the camera projection is active inside of PS, so I can precisely see where to move my geometry such that it nicely aligns with the color information.
Some suggestions for such basic tools: a Cut tool, an Extrude tool, a Move/Rotate/Scale tool for vertices/edges/faces