The new expand/collapse functionality for hierarchies on rows is a great improvement!
It would be helpful to have the same functionality when a hierarchy is pivoted to the columns. This would give users more flexibility in how they structure a view while still being able to hide or show detail.
It would also be useful to expand and collapse groups of line items. For example, in the screenshot, Line Item 1, Line Item 2, and Line Item 3 roll up to Line Item Summary. I would like to be able to collapse the three detail line items so that only Line Item Summary is shown, and then expand them again when the detail is needed.
This would make larger grids easier to navigate and reduce the need to create separate summary and detailed views.
