The new multi-pane layout of Discovery Hub is great, but it has a bit of a problem in that the windows aren't context sensitive in some cases - what happens in one window happens in all windows.
An example of this is creating relations between tables. Doing this with the same database open in two panes makes this process much easier and faster! Except that creating a relation cause the UI to snap to the relations node of the table where the relation has been created. It does this for all panes and windows that contain this table, even though you'd want it to only happen in the "destination" pane and nowhere else. Honestly, as a more advanced user I find the "snapping" functionality to be frustrating. But if it has to happen, making it happen in all windows and panes makes the new layout much less useful for tasks like creating relations..
Another example is opening tables in new windows. If you have multiple panes open, and open tables in a new window, if you close any of the panes, all of the open windows close. It would be very helpful to close only the windows that were opened from the pane that's being closed.