Perhaps I'm just not seeing a better way to do this.
In my project, I'd like to have some flexibility with Portfolio's hierarchies, in that, I'd like to have Initiatives, but with the ability for them to have both Epics and Stories as direct children.
Initiative
Epic
Story
Sub-task
OR
Initiative
Story
Sub-task
Does not seem like that's possible, and the doc doesn't provide any added clarity on such a configuration. Perhaps I can simply use Epics and don't need the Initiative level?