An interesting and different composition. I like it. It would have been nice to have front face of outcrop in focus as well but I don't think you could have done it with the long lens.
Rain drops are sometimes awkward. For me in this one, I would remove them as well as possible.
Love the bird, especially the eye. Not that excited about the perch. Something about that out of focus rock sticking into my living room. Don't suppose you could have moved the rock. No, just kidding. In my experience, sometimes a good bird chooses a difficult perch and that's what makes this so much fun. Thanks for sharing.
I like the pose and the green BG. I'm used to seeing these guys against an ocean backdrop. Not crazy about the OOF rock. I'd go with a tighter crop that eliminates as much of the OOF portion of the rock as possible. In the field I might have stopped down a little or thrown on a 1.4x to deal with the left side of the rock.