Not sure what you mean by Outernet Librarian. Did you mean Outernet Library? Library is not complete, and not very large (I think it's around 1.5~1.7GB right now). We are experimenting with new ways to put more content on it.
Raspberry Pi revision 1 model B+. You've read correctly about revision 2. It's been postponed due to development of other things.
I'm not sure what exactly is meant by this. Could you quote the exact portion of the text that discusses the topic?
The 'data for lantern' is used to loosely refer to low-speed broadcast. In that regard, filtering refers to including only content that is suitable for low-bandwidth consumption (e.g., omitting video and other heavier files).
We can't provide canned advice on dish/location combinations. 90cm dish is deemed safe in most cases, but that is not even a guarantee for reception in all areas. Generally, if you live in an area with good signal, you can get away with 60~70cm dish, average is around 90cm, and on fringes you may need 1m and larger.
I can't say I've used satbeams before, so I cannot answer these question. Maybe someone else on the forum would know more.