that would be an excellent feature reducing programmers effort to map 3D hotspots to xy-plane. I have gone through the math hell recently when I was working on structural steel sections lib part trying to 'catch' all hotspots of rotated and inclined beams in space. It took me 2 weeks to figure it out.
Also, I found the problem with having 3D hotspots separated from 2D rep's when an active hotspot of an inclined beam (sliding along the beam edge) in 3D can not be defined in 2D because of the cosine factor of inclination angle that affects values of a particular variable.
::rk