Opinions as I say, are a bit like armpits. Everyone has at least two...and most stink. So take this, and take from it what you will...and I'll feel none the worse for you to discount any of it...
I don't mind the color...but, to my eye...there is too much "sameness" ...not enough variation to create intrigue...so for one, I created some shadowy area on the left (quickly...with photoshop)...as one example...which helps isolate the form more from the background, bring it forward and cause more depth illusion...
Another note...the anatomy of the forearms is not quite right I suspect. Might want to check your references...
lastly...part of intrigue and variation is to grab the viewer's eye and pull it thru the work in a compelling visual balancing. Formal symmetry is trite and overstates the obvious causing less viewer appeal. Asymmetry better...and one thing I note is the crop or view does not create a focal point specifically.
A typical thing any artist can do...is set up a rule of thirds in designing their work. Where the vertical and horizontals are divided in three equal areas creating four juncture points. The focal area of greatest interest if located on one of the juncture points tends then toward an asymmetry that will carry greater intrigue...