A mute button for the people column so you can have people columns for other purposes than assigning.
At the moment our boards have manually created status columns with names in them to keep track of who requested an item, stakeholders of an item, or who has a specific function in a board. In those cases we dont use the people column because it assigns, sends a notification and creates items in the My Work view. We use those columns only specifically for assigning.
In hindsight this made the boards maintanance unfriendly because you have to manually add people in those columns. The people column would be a lot more useful, also now with the forms if it didnt automatically function like an assigning column. Muting the board notifications will also mute the assigning columns so thats not an option.