Just finished the book last week (yes I'm behind the mass crowds)
1) I like to think Dumbledore as Obi-one, since I also like to think he isn't dead necessarily. He may have needed to show Harry that last bit to set him on his course, but when V is defeated Harry will understand a way to bring D back. No from death to life, but something else.
2) Snape is a hard one to pin point. He could still just be in on D's wishes and it's actually bad. He hates all those associated with Harry, but even if false and fool hardy I like to think Snape has good in him somehow/someplace.
3) I loved the relationship building, but there seemed almost too much of it. That is the one downer of this book. Till the end there are love battles going on, but not the normal action she has been putting in the first half of the books. That could just be since book 7 will be so much action, and she wanted to get in the last really good hit of these are people relate to them.