I have just set up my first membership site. (It's under a maintenance screen so I can't give you the URL). I'm not using multisite or BuddyPress. I have set a free level and a premium level and and have made shortcodes - but I don't think I have the shortcodes working properly as the content I have wrapped in 'free' does not show. The message that I set for non-members repeats several times which is a bit odd.
I would like to also have a life member level of membership that I can give certain indivuals - not through the paid subscription screen. I cannot figure out how to do that.