I will add some coastal photo ideas from Houzz here, look at the colours, accessories, rugs and curtains etc to get some ideas. Having said that I would remove the picture about the TV area, remove anchor and ship steering wheel and add these two item either side on wall of fire area if safe enough.

Next to fire place near window, you could add a small book case and add some books related to the coast, add large seashells for display in a glass bowl. You could do a lot. Painting the room white will bring out the colour of the fireplace- make that area a reading & sitting area.

http://www.houzz.com/photos/query/coastal-living-rooms

http://www.houzz.com/photos/query/coastal-living-rooms/p/8

[https://www.houzz.com/photos/florida-beach-cottage-beach-style-living-room-miami-phvw-vp~4927364[(https://www.houzz.com/photos/florida-beach-cottage-beach-style-living-room-miami-phvw-vp~4927364)

[https://www.houzz.com/photos/cape-cod-beach-style-living-room-los-angeles-phvw-vp~2993582[(https://www.houzz.com/photos/cape-cod-beach-style-living-room-los-angeles-phvw-vp~2993582)

[https://www.houzz.com/photos/contemporary-family-room-contemporary-family-room-baltimore-phvw-vp~1010122[(https://www.houzz.com/photos/contemporary-family-room-contemporary-family-room-baltimore-phvw-vp~1010122)