Hi, I think the design and workflow of Sidebery (https://addons.mozilla.org/en-US/firefox/addon/sidebery/) add-on could be the reference for Firefox native Vertical Tabs implementation. Maybe even adopt the code and development, if that's easier.
It would render "List all tabs" redundant and give Firefox View the opportunity to focus on multiple-windows navigation, leaving tabs management to the sidebar.
The vertical tabs right now being tested in Nightly are more primitive in comparison, and there seems to be no good reason to reinvent the wheel. Sidebery is under MIT license, so that shouldn't be a problem
Just an idea. Hope it helps. Wanna hear what other users think. Kind regards! ^_^
