Feature suggestion: camera animation in demos
Basically, this is similar to envelopes in the map editor, but instead, you can keyframe the camera path during a demo.
Throughout the demo, you could add points where you want the X and Y to be and the camera would follow the points. This would allow for a pretty smooth free-cam rendering of whatever demo you want.
Also, it could even have the zoom level animated so you could zoom out if there's a big part ahead.