After I post the last update, J asks me to fix and develop more. The problem is that the image is still too flat and need to make some depths more. Moreover, J wants his tower very outstanding and the main source light is come from the back of the tower so that the mountain should be more darker and have strong rim light from the back.
Therefore, I try to fix as he recommends and this is the current version that I just have fixed.
I make the painting has stronger contrast by adjusting the contrast level in every layer that I paint and paint the stronger shadow and rim light in every object in the scene.
While I am still waiting the response from J (J has already got psd. file of this version), I have started thinking about ideas for senior project next term. I have some couple ideas but still cannot decide which one is more interesting to develop.