Abhijat,
I think that this composite is troubled a little in execution as there are perceptual issues. The red/orange and black are a good combination but rather overwhelming a choice. It can be kitsch! If there are going to be figures on the beach, they should be well silhouetted or just smudges or else clearly drawn. Here we do not see clearly the shapes and the movements are not lyrical. The light from the sun does not fit with the shadows. Consider putting the sun just to the right of the girls long flowing hair. I know that you are not so perfect yet in Photoshop, but the sun could be moved over to the left. Then one would need to brighten the edges of the people backlit by the sun. not a lot of work really, but something that would give you great satisfaction if you tried to fix and succeeded, which I'm sure you could easily accomplish.
Personally, I would steer clear of any black matts for framing images unless you have a special well thought out plan that needed it for full experience.
Asher