I'd start by adding some living green via plants up the middle of the table.

Just colour that big wall, as everyone is sugggesting OR you could paint that big alcove space in the ceiling instead OR you could paint the wall and the alcove bit of the ceiling one colour, but the boxed in walls - in that space - a different colour. Hope you know what I'm talking about! Good luck.

I work as a colourist and the easiest method for a upmarket look is to choose an exact colour to match one of the colours in the tile. I would take the tile to a paint shop and get the colourist it match exactly one of the greys in the tile. Make the depth of the colour a light version. All white walls are on the way out. Lappatto tiles usually have some texture as they are semi polished. This is the latest look in tiles as they give a shine without the maintenance of polished porcelain which had been in. They are usually less slippery than satin or polished tiles depending on the brand.

Dulux Whisper white or China white. Just grab sample pots and paint large pieces of cardboard, that way you can get a much better idea by moving them around the room and in different lighting. Will make you more comfortable with your choices before investing in the paint.