I like this idea.

To a degree, it is already possible if people make use of live-streaming services of their game on the internet, although this creates an additional load on PCs. Some people are known for doing such streaming of their playing, such as Doctor Mog.

Running it through the client would be far less data-intensive on the end user and absolutely awesome if you could roam the dungeon as a ghost. Of course, a lower priority for SE, understandably.