Shutters sound like they would be a great addition to your new almost at the beach house. Is it an open concept? If so while you can change things up a bit you'll want to repeat some element and ensure that everything looks great together. Even the rooms you're thinking of putting drapes in might benefit from shutters or wood blinds for both looks and light/privacy control. Also be aware of how these windows will look from the outside. When choosing fabrics look at your existing furniture for inspiration or a piece of existing art or if buying new furniture think about the windows as you do. Everything in the room ties into each other. Ideally you would have swatches and samples of every finish in the room from flooring to window coverings and everything in between including wall colour, area rugs, bedding ect to help make your final decisions easier.

I would go with a gold or yellow ... of course I happen to love teal/ turquoise and gold/ yellow together. Something in variations on the photos below... maybe some pink accents if you have a girl or lime green or blue accents if you have a boy.

this room has one large window which takes up most of the wall facing north.quite a bright bedroom. would it look funny having a green, black and 2white walls? I just want to tie the black furniture in with a black fixture somehow. maybe you have other suggestion?

Textured linen or with a subtle print wont date. Feature walls make a room smaller as they jump out ar you. Wouldnt recommend. Get some interesting art or craft. Pick up colour with accesories