thank you for mentioning this, i didn't think of it! i decided to do a quick search and it seems you can set passwords for your content on the site? and they can be set to expire after a certain time. this might be worth looking into afterall then...

as for smashwords, it's probably the only other site i've been considering lately! i'll have to double check their content guidelines to see if they'll take some of my pieces, haha.