That's a great point. And since people aren't running dedicated machines, only paying for the requests that happen, it could even be cheaper than spinning up your own server. Interesting!
Super curious, what would you use the virtualenv for? Each script run happens in its own container. Is it to import your own libraries that we don't support yet?
Ok. I wonder if it needs to be optional if we let you create private, environment variables for your script. Wouldn't show up on view source. Or maybe we do both :).
Have a look at datawrapper.de - as far as I remember, they use handsontable for data table editing. Datawrapper visualisations are used by many journalism-related sites around the world - seems to be a successful model.