I like the pic but I find that all the colours are almost the same which gives the picture a dull and uninteresting feel. I think that you could maybe change the colour of the back round to a more vibrant colour but not a colour that is so bright it will take away from the pic. Also you could darken up some of the outlines because I find that the also make the pic look grey. If you do change the colour I would suggest maybe a light blue for the background. Great job
Blending is good on most images. In this case, it isn't so much, because it is overdone. The color palette could work if you gave the girl a splash of color so it stands out over the interesting pattern in the background. Otherwise you have an image where not only are you distracted upon looking at it, you also quickly lose interest because of the paleness of the image. Also, integrate some depth into the background; it is missing here.
I would think try and new background personally. The middle line there makes it looks like the background is a copy/paste of each other and well thats actually fine to have just how it looks atm doesn't look to well. I'm also not that much of a fan of the graininess to it. Also check her left shoulder as the blending doesn't work well with and looks abit lazy. The bit of lighting that is above her is nice and would keep at atleast.