Left attack over ladder seems fine as a backdoor, the gate is okay too (Although i think people will just open the gate, destroy the next one and then rush flag), but the right one is kinda useless, because it's a longer way, you have to destroy the door and then you have to walk all the way to the other side of the gate to get open it. That is my only concern though, looks good otherwise.
OH, one thing though: Remove the visible purple part of the mountain. I don't care if you have to make a purple background for your signature, but don't let that ugly purple mountain be seen by the players (Unless they are checking the map in spec, but whatevs).
Gotta give me a name, too, otherwise i will name it myself and i don't think you want that to happen =D