You need to post a picture of everything to be considered for any suggestions.

The window sill will be Stuccowork colourtrend like the walls, but not sure if the shelf should be the strong colour of the bed Long weekend Colourtrend, or just kept natural and varnished or even painted the same as the walls Stuccowork paint? Find it hard to visualise

I want the shelf a natural wood colour but your picture makes the wood looks flat, needs a bit of toning, maybe a satin or matte varnish would be enough to brighten the wood.