We have and use quite a few custom fields in Jira. This can create a large list of custom fields for data import. It would be helpful to have the ability to know which custom fields I am importing into my accounts for report drop down filters, and which are being used in a custom calculation. You could either build a report in Usage statistics for this, or on the custom fields import area, add check boxes that I could update and manage myself. one box for custom calculation use, one box for filter use.
I hear you on this. Tracking custom field usage in the reports might not be easy. I created a feature request to highlight custom fields in import options if they are using in reports or calculated members.
Daina / email@example.com