Just wanted to recommend a great picture book your DD might like titled 'Hello Baby'. It is a beautiful book about a home birth in a family were there are other children present. It has a really simple story line with great pictures. It sounds like she is really interested in the up coming birth so it might be of some benefit in terms of preparing her. The lady down the road from me gave it to her DS (5) and DD (7). They loved it.

Also some of the behaviors you mentioned your DD displaying are almost identical to those these kids started showing about a month out from their sisters birth.
Good luck for your home birth, every home needs one.