I singlehand 99% of the time. For fifteen years, I sailed a Catalina 30 with a conventional mainsail cover. I recently moved on to an Irwin 38 with a center cockpit that has a full enclosure. The only thing that makes it possible for me to handle what seems like an acre of mainsail is a system that is exactly what you describe. Mine is made by Mack Sails and they feature what they call The MackPack on their web site: http://macksails.com/mackpack.htm
Take a look. It will answer many of your questions. While it doesn''t work as perfectly as the model on the web site, I am perfectly happy with it. All it takes is a few pokes with a boathook to move any errant dacron to its proper place so that the cover can be zipped shut.
If I bought another boat that didn''t have this system installed, I''d get one right away.