So, you are looking into writing your own Launcher? That would be great. Perhaps you can take a look at ReLaunch
, see if you can use some of its ideas? It's an open source project. The GUI in ReLaunch is a bit rough, but I like the idea of being able to associate file types with application targets, and change those associations.
The Sony's launcher is not bad, looks very nice, but it's limited to all things Sony. No access to Android Settings, no "Add Drawer", no support for ebook file types other than the ones already supported by Sony (epub, rtf, txt).
Basically, my ideal launcher would look like Sony, but with access to those extra features, i.e. App Drawer, File Manager, book type selection...