I'm relatively new to PlantUML and can see how powerful this is. However, one of the things I can't see is how to create a "Feature Board".
So, imagine a "Story Board" layout. It's effectively a grid.
Along the top are boxes which are "Headings", e.g.
[Search] [Add to Cart] [Checkout] etc. Think "Epic" or "Feature"
Then, underneath each of these headings (linked with a vertical line) would be the "user stories", e.g.
There would be a way to give each box a back-ground colour, so one could colour "Phase 1" in one colour, "Phase 2" in a separate colour, etc, etc.
I mentioned a grid layout - it would be great if there were an option to align each row, but this is probably not a "must have" because there should be no relationship along the row, just vertically.