Mets? No way. Until their starting rotation can stay healthy over a full season. Even still, I take the Nats rotation of Scherzer, Stras, Corbin, Sanchez over the Mets. Nats have a much better lineup than the Mets as well, even without Harper.
Phillies? It's a close one. Nats rotation for me gives them a slight edge.
I think Atlanta is the team to regress the most in the NL East. Don't see them as being the favourites.