Harmy said:

As to the menu, I was actually thinking about MultiAVHCD but I'm not sure what its capabilities are or how complicated it is. I do have Adobe Encore, that came with Premiere CS5.5 but I can't quite seem to figure it out.

MultiAVCHD has the advantage - alongside being free, of course - of making completely compatible BDs from a range of different sources (including existing BD folders). Having said that, I've found its menu interface limiting - it has a somewhat fixed toolbox, which is fine for basic front-ends but not hugely flexible for tailored presentations (e.g. audio selection is only available via a pop-up menu with preset design).

Encore, on the other hand, is far more versatile but doesn't like open-GOP x264 video - it chokes on import (as I found when attempting to make a fancy menu for your own SW:D). If we can overcome this in some way I'm happy to lend a hand - Encore's a fiddly mistress but great once you get the hang of it.