Looks pretty neat so far.
I know you've noted this, and I'm not sure as to how much of a possibility it would be with tiles in mind, but the rock should follow a more natural flow, if facing to either side, left or right, it should be slightly angled, like the mountain in the background; somewhat like this:
A more suitable and subtle flow for a game would be somewhat like this I suppose, but take this as you will, this isn't a rule or anything.