I'm NO expert in design, please take my comments with a pinch of salt. I'll just tell you what I see.
I find my eye is draw irrevocably to the grapes (light against dark and all the lines), but then my eye wants to go to the horse's head which is near the other edge and crosses the 'dead' patch in the middle as though it's split and there are two points of interest. The split is the problem I think. We cannot look at the horse without looking for its head. As a marketer once said to me, 'the eyes engage.' But it's not a point of rest because the rest of the painting pulls me back to the grapes.
i like the setup.. can you also have a look how the setup looks with the light source from top-right and also top-right-a little to the back , maybe some some beautiful shadows appear. The grapes individually look great, but together form a boxy shape that is unlike its graceful tapering look, so, may be adjusting the grapes a little...
Hey, i know you said you were starting over but I would like to say that the shadow of the horse and the green reflection of the vase onto the background were very effective
Comments
I can't get beyond the harsh light. The objects are all at the same height of interest.
The grapes individually look great, but together form a boxy shape that is unlike its graceful tapering look, so, may be adjusting the grapes a little...