I was going to ask about the Prefect situation since that would help things move along. If Harry and Hermione are given more time to talk than their previous brief encounters it might help make Harry want to branch out and give Slytherin the make-over he's been thinking about giving the House with the bad reputation. He may want to consult Hermione there since she knows about the history of the school and is fairly observant. And it could tie into the three wanting to make the DA together. Maybe Ron ends up being part of the I.S with Umbridge.