Personally I think that VJ-ing is all about human intuition and carefully listening to the music. It's tricky to improvise and find visuals that match the given mood, layer realtime NestDrop visuals and pre-rendered visuals together, all while trying to keep things fresh and alive. I don't think it's a skill that can be automated with the same level that a person can pull off. NestDrop just creates visuals which respond to the beat, it's just one piece of the puzzle... Not an utter solution.