For the fireplace inserts go ahead and do the green order a second set of panels that you store that are more neutral. In 10 years or five years you may not like the green anymore. It's possible you won't have access to different colored panels at that time. As for the color I like the ideas of going into those silvers it would coordinate very well with your blue couch and it will pull the blues out of the curtain panels. For the wall coloring use the warm golden color in the drape. There is one piece of the flower that has this color and it will balance the weight of a dark couch. If your room is small don't go too dark in this color. You could use it on the main wall and pick two shades lighter on the other three walls.

I would use a bookcase unit with closed doors on the lower half and not too high. Wide and low maybe. Closed lower cabinets are great for toys, games and will not clutter. Open shelves tend to get cluttered after a while. When displaying books, use in stacks standing and lying down. Open space between groupings, not all lined up in rows. Add some decor items sprinkled among the books to give the eye a visual break. I would choose a horizontal art piece for the chair wall. Add some art on the long TV wall leaving a lot of bare wall between the TV . and the artwork between the corners of the chair wall and the window wall.

I would avoid using dark colors in a room with wood paneling as it would make your space gloomy. You also don't need to match the dining room set. I would go with a very light and fresh cream with very light brown stripes. You could also choose something like this (https://s-media-cache-ak0.pinimg.com/236x/57/8f/6a/578f6abfb4e7b991e594b64cf4f2c174.jpg) to add the blue to the mix and have more colors.

Yes, the brown wall is actually deep purple (aubergine). The carpet is more dark grey than brown. It is not a commercial place, but a large family home, and all the extra chairs are around because we were about to have 22 in for dinner, so the table was fully extended to it's 6metres! (The lounge is totally separate to this room, this is family space, so has the old sofas for sacking out on) But I really appreciate all suggestions and comments as it would be good to pull it together, even when entertaining so many. Cheers!