The goal of this would be to force the users to put issues in a hierarchy rather than mandating that every issue is important.
It seems that your are looking to define ranking more than defining a issue hieararchy.
what you can do is to create a rank numeric custom field (global context) and to use it to define the rank. At that point you could use it to order your filters.
project = XXX order by RANK DESC
If you are planning to install JIRA Agile it provides a great ranking feature usind drag and drop (it uses a rank field as well behind the scenes) https://confluence.atlassian.com/display/AGILE/Ranking+an+Issue
Every team in the world is unique, and so Atlassian believes that each and every team's best way of working needs to be molded to their unique circumstances – ...
Connect with like-minded Atlassian users at free events near you!Find a group
Connect with like-minded Atlassian users at free events near you!
Unfortunately there are no AUG chapters near you at the moment.Start an AUG
We're bringing product updates and pro tips on teamwork to ten cities around the world.Save your spot