Nice work. I especially like the domestic font, it looks great in the startmenu. I tried the patch and it works for me in the 4 modes, but it was somewhat hard to test when one doens't have 4 themes that are exactly made for it. So maybe you could provide a theme for each mode so that one could test it easier?
The changes to the code are very hard (or takes a very long time) to review since there's no comments about why you made the changes. Like what is the cache parameter you added to render::image? Why is it needed? It doesn't have to be very long, just an overview could be great. With the description it will also be easier to see if the code does what is expected from it
Regarding integrating it then 1.1.0 is really the way to go. The way I see it is that the menu structure could be provided directly in the theme then that would be the best and most flexible way. Maybe some of the code Fredde has for building menues in the python plugin can be used? A second option would be to provide a new startmenu view as a plugin. It seems that the different startmenu's have a print and a generate function, in that can one should be able to generate a interface and let the startmenu plugins register themselves on load. Like the audio players does.