What are the minimal rights needed to see the Wait Stats tab in Plan Explorer Pro?
When you're generating an actual plan, the way that Plan Explorer captures wait statistics for your batch is with a targeted Extended Events session. So, the login accessing the SQL Server must be able to create that session. This requires CONTROL SERVER on SQL Server 2008 / 2008 R2, ALTER ANY EVENT SESSION on 2012+, and of course is not possible on <= 2005. If the user lacks the permissions necessary to create an Extended Events session, they will not see a Wait Stats tab.