We use our Fixed Versions as releases. Our Releases can include items from multiple JIRA projects. We would like a way to create and manage Fix Versions across multiple projects. This would cut down on Administration and user error for releases and allow us to do a search for all items in a release without having to write custom queries.

My suggestion is to make Fixed Version like a Group that multiple or single projects can join. You would need to add a new Permission to the Permission schema for "Create and edit Fix Version" removing this from "Resolved Issue" (These should be seperate anyway) The Project Role Administrators would be able to join or remove Fixed Versions for that project but would not have the ability to add or delete new Fixed Versions unless they were granted "Create and edit Fix Version"