Allowing the mapping between JIRA project and BitBucket repository would have the following advantage

• While clicking on "Create Branch" in Development Panel, it will automatically suggest the repository that is linked to the project.
• Remove the list of repositories that the user/team has access to but not linked to JIRA

Else, we could have the communication to be a step smarter with automatically suggest repository during "Create Branch' from the last commit to the project.