A few suggestions regarding the colours.
Have you tried darkening the stone textures in an image editor? Just, for some reason the well looks a liitle pale.
Have you considered aging the stone textures by adding some moss/lichen/slime to them. You would do this by using layers in your image editor.
As thatch ages its colour tends to go greyish so you might like to try that or maybe darken the colour or both.
TR