Using a Terrain Object... as a Terrain brush

I've always wanted to use terrain generation tools, but since my world is huge and ever evolving, I've never known how to integrate generation correctly. One idea I've had is to generate terrain using some tool (such as https://github.com/CyanCode/Procedural-Terrain-Generator), then using that generated data (heightmap, splatmap, etc) as a literal brush!

Is this something that is possible with the new Terrain System brush API? I imagine it would be! Is this something people would be interested in using if I built it?