I think there is a Montessori in Olinda, maybe it's Steiner not too sure. There is a Farmers Market at Yarra Glen. The hills are beautiful, we live in Mt Evelyn and we love it. One thing I can remember about driving up Mt Dandenong in the winter is it gets very foggy and can sometimes be impossible to see the road which is very windy.
DH grew up in Mt Dandenong and would love to live there again. As for safety, you can get creeps anywhere unfortunately . Would DH consider catching the train into work?
Good luck, I think you are making a great choice.