Really like the concept and demo. And it looks well made! Just out of interest, is this something you did as a hobby/for fun, or was there a particular use case you were addressing?
But in general I want to solve a problem: a lot of people know SQL which is actually powerful to wrangle data to prepare it for visualisation and analysis. It can't be simpler than drag-and-dropping a CSV into a browser, producing a result set and consuming it by the visualisation component (now Plotly, but more to come).