Only 2 hours? Cmon.. you can try harder than that... try a week on a wall
No, really.. seriously.. imo could be more imaginative, needs some blow u away factor, there have been so many really kickass orb walls done that one really has to do something very special to make a dent.
I'd try perhaps adding more detail, perhaps adding some more highlights to the orb part... light can come from many directions, bounce, slightly modulated colors, depth of frield... etc...
If all else fails... try some boobs !