Most important to us is that there is a tree, but I think any of the proposed interfaces is viable for browsing it.
Do I understand correctly that this is not replacing the current object/subitems list in the admin, but more is intended to replace the expandable left tree in the legacy admin? In the subitems list it is important to be able to view metadata (content type, date, creator, etc.)
In regards to the usefulness of multiple interfaces, as the number of content objects and editors increases in a site it will become more valuable to have different interfaces to serve different needs. It is reasonable to launch with one view and add others as needed to serve specific use cases.
We wrote about our opinion of the importance of a tree to editor UX here https://www.contextualcode.com/Blog/A-CMS-with-a-content-tree-provide-editors-a-better-user-experience