A picture like this is hard to do, and you have a good foundation here. Things that come to mind are, that with the stretched fabric you have blocked the horizon, and created a new one. Unfortuantely since her arms are not exactly level it creates the illusion that the camera is tilted. The eye tends to slide down the new "horizon" and off to the left of the picture. A shorter depth of field would help focus the attention on the angel, the detail in the background competes a bit. Lastly soft focus or soft lighting would help a bit here also. Angels are mystical creatures, and the lighting here is very direct, almost harsh. Good control of the exposure and contrast. Nothing is burned out or muddied.
I like the general mood and lighting of the shot but I think you could improve the position of the model's head. I think it might be better if her face was pointed slightly more to the light and her chin was up elongate her neck.
But then again... what do I know. It's taken me >5 minutes to complete this comment because I continue to be drawn back to the shot. So there's something captivating just as it is. Nice job!