When I land on the Suggested / Featured sites page in Office 365, how can I see ALL the sites that I have permission to access? All I see are suggested and frequent but that's not a full list of my sites?
In the search box on top left corner in office 365 SharePoint home page, type "contentclass:STS_Site" and search. It will give you list of all site collections you have access to. If you need to see all site collection + subsites , search for " contentclass:STS_Site OR contentclass:STS_Web"