I think that is related to role capabilities.there are capabilities options for access control in most of plugins: for example:
As to Media Library, there is solution too to control: https://wordpress.org/plugins/wp-users-media/, the user only can access the media library which uploaded by himself/ herself if that plugins is activated, what need to do is to make decision whether we should integrate that function in Hype Animation plugin.
As to the plugin update, I will test it tonight since we are working on it daylight, and let you know the test result.
MarsEdit is great tool to publish post, but we are always use some plugins to support frontend post like:
this one was the most popular one:
but recently, we are very likely to intergrate frontend post with Buddypress if there is a social community on site with a plugin: