I like the concept that is going on for this piece but background looks a bit empty and flat so I added more of the same towers to help with the depth. The environment is also a bit confusing since it's quite vague as to where the character is standing, so I just made it feel like it's just in a sea of clouds of some sort. For the character, I adjusted the proportion a little bit cause it seems like the the head and torso aren't really connected. I lowered the head a little bit so that her neck feels more connected to the shoulders. For the lighting on the face, the light will definitely shine on the left side of the cheek too since you already indicate that the light hits both her eyelids, so I just added that. Added highlights to the hair and clothes to make it look more rendered. Adjusted some of the shapes and curves of the hair and clothes to make the silhouette more readable. For the water effects, I make it more dynamic and increase the depth. Making it look thicker and bigger when it's closer to the camera can help with the depth of the piece more. Also, use the environment colours to paint the transparency, reflective and refractive effects of water. If you are unsure how to approach it, study some of Kan Liu(666K信譞)'s works, that should help with some understanding on the rendering of water effects.