It would be useful to preview and manage panes the way we manage tabs in Chrome. This interface could be similar to Chrome’s tab organizer called Vertical Tabs, at the far left end of the tab bar.
(Half Implemented: be able to set the order of panes.)
When there are multiple panes open, press the three-dot menu at the top, right of a pane. Select the menu option “Move Pane Left” or “Move Pane Right”. The options will be greyed-out if not possible (e.g. “Move Pane Left” will be greyed-out if this pane is already all the way to the left).
(You can also access these via the command panel. You can also set custom keyboard shortcuts for them.)