I ended up like this...

Although I still need to adjust colors on dark part of water, this is how I ended up. This is the situation impressionists would use fat short strokes and let the primary colors get mixed through viewer's eyes. Instead I used a smaller brush (#5) with mid-length strokes, which created more realistic outcome. I guess I unconsciously intended it. Since at least values are much closer to the final, I'll go back to the rocks again to match value-wise.