I find it interesting, and played with it for awhile.  Wasn't sure where in the band, or band width, was showing, but comparisons with the waterfall soon rectified that.
One thing that might help, the background noise (noise floor) does not match that in the waterfall it seems.  I need to adjust the waterfall to see the noise a bit to help in locating signals on the 3D - maybe some freq numbers, or other locating device could be added?  And/or a slide to adjust the background noise level in the 3D separate from the waterfall one? Using the "Auto" button on the left of main panel makes the 3D have zero background to help see the weak signals, so the suggested slide or a bit more gain in the base 3D setting may be of assistance.
Looks like a nifty addition, not sure if I will use it a lot, but interesting to play with.
Thanks for the toy Simon!