Expand the group filter to be able to search based on any YAML field). Not everybody is using tags for this purpose. Plus it will open whole new possibilities to make the graph view usefull.
I’m a heavy YAML user; #tags not so much. (Example YAML tags: Type, Client, Project, Status). This would make Graph View much more usable. I’m currently looking into getting similar functionality by using plugins but I think native graph view support would be better.