I'm liking it. I have a couple of suggestions though, take them for what they're worth.
Another defender you may want to consider.. Hover Barrier. It can block nearly anything and is fairly cheap to cast, plus helps on your defender count for the Doorkeeper. First thing I'd look to cut is the Farseeks. The only thing they can grab right now are the islands and Overgrown Tombs.. not worth it IMHO. Only way I'd keep them is if you added more shock lands in place of the other dual lands.