One reason I prefer Apple Numbers to Excel is that in Numbers you arrange tables on a canvas. The tables can refer to each other. I think it makes it easier to work with, for example, an input table and an output table because they are separate entities and not just different ranges on the same grid. It’s similar to how some websites enable you to configure a dashboard view of multiple tables and charts.
Your presentation reminded me of that, specifically the view of how you implemented the tool in itself. But you’re using one large table rather than a collection of tables on a canvas.
I’m wondering if the Numbers approach might work better. In particular it might be more natural for dynamic arrays because they would not “overlay” a range of cells. They would be their own dynamically resizing table on the canvas. This might lead to something like Spreadsheet 2000: https://en.m.wikipedia.org/wiki/Spreadsheet_2000