Actually, I envision it at the data type (column) level.
In Excel/Sheets the user can set the height of rows at the row level. In Coda, I want to set the height of rows in a rich text column at the column level. The height of the entire row would change, not just the one cell in that column. And because it’s being set at the column level, the height of all the rows would change.
In a rich text column format modal, a slider could adjust the size of all the row heights in that column simultaneously (in bulk) – they would all get shorter or taller as the slider is adjusted. The height of the entire row changes, and all the rows change in height.
Hope that makes sense.
There are obviously lots of “what if” scenarios to think through, but this is just intended as a starting point.