A “directional room tone” can be useful and it gives a nice sense of space even if it doesn’t move (a bit like a skybox background in games). It can work for ambiences like “there is a storm in the north”.
Two stereo files can be used, and the “L/R Surround” panner on the output with its Direction automated automated to achieve this.
Making the rotation envelopes to Event Orientation parameter is a bit tricky. One envelope can go from -180 to 180 in a linear fashion, but the others need to be cut and ‘sawtoothed’ to ramp wrap around in the right direction. Discontinuities are inevitable.
Being able to rotate a 4, 5.1, 7.1 surround panner with a single parameter could be a cool feature. Or a “pan rotator” plug-in.
If you use a Scatterer in an event that is locked to listener position, but its orientation is locked to the world, it can generate a room tone with rotating spatiality. The scatterer can be set up to play back randomized cuts of a loop that fade in and out. You can do this by inserting an Event Sound into the Scatterer playlist, and placing a loop with a fade in, fade out and Seek Offset randomization (and also pitch randomization, why not) to generate a surround soundscape that rotates as you look around.