Perez does not have any kind of track record, so I am not building an order around him. I am fine with Canha leading off and Greene batting second. Over the course of a season, Greene would lose about 36 PA by batting 3rd instead of first.
It's fun to talk about batting orders, but Having Geene bat third instead of first is probably worth maybe 5 runs over the course of a season and I am not sure it would go in the direction you think. In the end, batting orders are not that important especially when you've got 4 or 5 .450 OPS guys playing regularly.