Satish the exposure is good as are colours, you may wish to lift the background a little - or indeed you may not according to taste.
Was the aperture f29, if so that would probably account for the softness of the image. I wonder of the focal point was somewhere around the wing tip on the right hand side, sharpness is better there than elsewhere. With the 100-400 I would have gone for f8-f11 with a cropped sensor camera.
Hi Satish. Good comments by Jon and Allen, above. The outer edges of the wings appear sharp, but the image is softer elsewhere. There is a lot of noise throughout. If, for example, you had used f/11 instead of f/29, you could have had the same exposure at ISO 400 with minimal noise (and better sharpness within your DOF). Just something to keep in mind the next time out.