Saw this story being posted, very good story, but did noticed the year posted so guess it has been abandon as the near 90% of the stories here on Ficwad have been abandon.
As for Snape, I say he should suffer and lose his magic and become a squib.
The castle should appear before dumbles in the great hall, accuse him of being a dark lord and strip him of his magic making him a squib and removing him as headmaster....