I really like the Elevation Profile widget. It's a great way for an end user to interrogate the data. I see a lot of potential to use this with non-elevation raster surfaces. While it can technically be done now, the output may be confusing depending on the data being used. For example, I work at a water utility and I would like my engineers to be able to retrieve an approximation of how the water pressure will change across a transect. I can make an estimated PSI raster and publish it as a service. However, I can't add it as a profile option as it's not an Elevation service. I could probably fake it as an elevation service, but the next problem is the display units. The widget only has options for standard elevation units, not custom units. The resulting display wouldn't be very readable without lot of extra explanations.
Additionally, it would be helpful in some situations to have multiple lines on a graph. For example, some areas will have a min-max range of PSIs, so showing both would be helpful.
Other potential applications would be measuring/displaying how air or soil pollution varies along a line, or how steep slope is along a transect.
