Great painting on this lovely figure. For me I would prefer to see without the background. I think it takes something away from this marvelous paintjob. With that said the background is a nice choice.
I can see Michael's point about lighting and planning your photos to match specific backgrounds etc. In full sunlight this figure would be in extreme lighting conditions with massive contrast between highlights and shadows. That's probably why these background images tend to look more realistic when you have a cloudy sky and the light is more diffused.
Great painting by the way Steve.