With the change to Topic management, we noticed a steep increase in unsubscribes.  We found that this was due to the unsubscribe link leading to an un-branded splash page that has a gigantic green unsubscribe button which unsubscribes to all topics.  The user can choose to click the hyperlink to change their email preferences, which will take them to the topic management page with our logo and details, but we know any extra click will discourage contacts.   Needless to say, most all of our contacts are clicking the big green unsubscribe button and not continuing on to the branded topic management page. 
Before the Topics implementation, unsubscribing customers were led to a list management page where they could choose which lists to unsubscribe to and there was a button on that page to select "Unsubscribe all".  How do we make the Topics management page the landing page instead of the big green unsubscribe button?  Follow-up question for bonus points, who thought that 'unsubscribe all' was a good place to begin the topic management vs prompting them to choose more granularly.