I like the problem you are trying to solve and I like the idea of the JSON data structure but I am not so keen on the language as JSON. I find it hard to read, which would be worse in more complex real-world examples.

I guess I would like to see the code as plain text. Packaging all the data to send as JSON is OK, and the code could be text in a single JSON data element.

Post a story to Hacker News once you get some experience using JSONScript with some feedback on how you went and how the idea evolves.