How about an option to buy a temporary PSN Pass - say 3 or 5 days for $1? That way people can rent a game and try out the online portion before buying it. Sony can choose to credit that $1 to a full-blown $10 unlock or pocket it as an additional service offered.
First, there is a PlayStation Plus forum here: http://community.us.playstation.com/community/play
Second, Sony takes feature requests and suggestions here: http://share.blog.us.playstation.com/