I like it, like it alot.
Really like all the sand space, wish I had more in mine as I tend to jam it full of rock.
I would add a bit more rock to yours though, seems a bit low on rock.
Keep all that sand space though, gives you room to do things.
As far as putting corals in certain places, can't help you there, I move my corals around until they are happy, so they basically tell me where to put them.
And I like to move things around just for the fun of it.