Had a good request come in via email:
To help out budding alliances, can there be a filter/list of all systems which don't have sovereignty?
If you've used the site, you will know looking at any region will show the sov levels of all systems and the alliance holding them. eg. Branch
Rather than browse all regions manually, I've added a column "NoSov" which you can click on to sort in the Regions list.
I hope that helps and keep the requests coming!