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 wouldn't drywall over the window. Take a look at the options for recycled brick, they may match better than you think.

I think it is awesome to give a piece of furniture a new life. It is sometimes a bit daunting to take a paint brush to a piece made from genuine old timber but if you are going to get many more years of life and enjoyment out of it I think it is better than dumping it. I believe it shows your love. jbof4 I started with a heat gun to remove most of the many layers of paint, (some are easier than others to strip this way). Then I used an orbital sander and sanded and sanded and sanded. You might also try liquid paint stripper although I find this very messy. I believe you can also get them professionally stripped. Good luck with the resurrection, go for it what have you got to lose.

based on the drawing, the wall where the bed is. HOWEVER, you mentioned that this drawing is not a true depiction of the furniture you will use and the wallpaper. if that is the case, i think the wall paper can work on either wall, it all depends on how busy this wallpaper is and how "plain" the bed is. if you go with a busy wallpaper behind the bed, you may want to keep your bed and bedding on the minimal side so that there is a good visual balance to the overall composition. if you go with snazzier bedroom furniture, then a busy wallpaper may be a bit much and you may want to put it on the other wall or use a textural option to serve as the bed's background rather then another focal point.