There is already a similar thing to downgrade a feature to an idea. The justification is this -
- We create an idea for a feature
- Once we understand it enough to decide if we are going ahead with it, we will commit resource to properly planning it and promote it to a feature.
- The early stages of the feature ("Under Consideration", "In Design" etc) are incubator stages where we start to specify a product and add requirements - no matter how crazy they are.
- Before we commit to a release, we will decide our MVP - we need a way of parking the features which we won't commit to. In some instances, this might lead to loads of requirements being converted to features which clutter up our board.