Currently there is an option to add epics and features to initiative in the "Related" tab of Initiative. However, there is no option to remove/unlink epics and features from the initiative. I am forced to go into each epic/feature and unlink the initiative one by one. Need an option perhaps with a trashcan button on each epic/feature to unlink it. Alternatively, provide a checkbox against each epic/feature to select multiple and take a bulk action to remove the selected set.
From my perspective, I'm not sure this is essential. The workaround to go to each epic/feature is pretty simple and usually you would need to assign the epic/feature to another initiative anyway. No vote from me, sorry!