After having to scroll multiple pages of angry, annoyed and attempted workarounds to this change I eventually got to the new comment section. Looking at the history of this change it appears that even in beta mode people were publicizing workarounds by removing themselves from the beta. This should have been a clear intention that it should not have become part of the major release and was not widely accepted.
Similar to many others, please allow us the ability to remove this as it takes up yet again more screen real estate for unused functions. An undesired change not accepted by the masses.
In addition, allow more customisability like we used to have. There are now "minimum widths" on the folder pane (inbox, sent ect) which takes up alot of space when you have the reading pane in use. If it continues, at this rate ill be downgrading to office 2010.