Show the profile on click
As a user, I would still want to view the profile of a person when i click on the name in the To or Cc. list. It was available in the older version - A right pane appeared and gave the profile, contact details and hierarchy of the person. It is very important tot see such details before responding to the email.
Currently, the click on the name collapses/expands the message.
Mouseover and wait performs the same action (as far as I understand).