Sudoku Tiles

I am undecided as to how to paint the tiles behind the clouds: with color or without or gray monochrome.I ended up graying the unobstructed sudoku tiles, particularly toward the top. I want them to look further away. Now the clouds look flat and fake. I will work on that tomorrow. It will be difficult because I will have to blur the cloud edges without smudging the tiles. Then there will be shading. Watercolor is just a never ending challenge, but when it works...wow!