The only advice I can give is that people will always put their hands on the top of the back of the chair to pull it out and push it back in, and it will get filthy. I say this from sad experience. So make sure the fabric is very easily cleanable.

Two years later... We ended up purchasing a 3-seater for wall opposite fireplace, a 2-seater for under the highlight window (leaves a comfortable space to enter the room) and an armchair placed diagonally opposite the couches. I've fooled the advice to pull the furniture in off the walls a little. We have just updated the fireplace with the (professional) installation of an insert wood heater and (DIY) replacement of hearth and tiles/timber mantel to conceal the brick while meeting the safety specifications of the heater (required a much wider/deeper hearth than the existing brick one so we removed and replaced with a slab of honed granite, and the minimum height for breastplate/mantel shelf posed a few design limitations). TV mounted above fireplace to allow for better furniture placement. Not quite the picture I had settled on 2 years ago, but works with the style of updates we have made elsewhere. Thank you for all the advice. before: After:

You can choose chairs either to match the curve of the table or the diagonal, chunkiness of the legs. Though that timber is going to be difficult to match. I'd go metal. You can contrast it with slim legs or go with the chunkiness .

Hi Jayrees, I totally agree with what Kat had to offer, I would suggest a non geometric pattern on the rug as the floor is already geometric, a light colour and subtle pattern if you prefer a pattern. The mirror should definitely be moved and I would consider a large light print to compliment the new rug and and drapes. It's a pity that the window screen blocks the view (it's a nice view) but the heavy screen is a necessity these days, I would remove the stickers from the glass to help with the openness. Just noticed that you have an air con in the room so you may be able to remove the screen.