Looking at the image again after a few days, my only real criticism is even though the intent is to present the Doctors in order, I think having Six in the middle, and the centre of attention, is somewhat inappropriate. I think having Eleven in the centre would make more visual and contextual sense. (But leave Ten where he is because I like the "spying on Judas" aspect - sort of like how in the BSG last supper photo Natalie the Cylon is shown looking accusingly at the character that kills her.)
Yeah, that was the first thing I noticed. Having the newest Doctor in the middle makes the most sense. Barring that, 10, 4, or 1 should be in the middle. Having six there, while good from a logical standpoint, makes him seem like the centerpiece, when he really isn't.
But maybe I'm nitpicking this thing to death. It really is quite nice.