It really depends what style you're looking for. You have brick walls and dark planks on the bottom, light on top. I would suggest making the deck into two separate areas with a strip of empty space to the stairs for easy flow.

Your brick has neutral tones so it would go well with most wicker, rattan and wood furniture.

Tv area is nice, but move the armchairs back so you have a better view of the TV and you still have a couple inches between the railings and the deck.

Your rugs give you less option to how you can style the area. Switching them out with a jute or outdoor rug in a more neutral color would give you more flexibility with colors and patterns.

I would add yellow as an accent, it would pair well with the green of the nature and the darkness of the planks. Sheer curtains added to the off white curtains would look nice too.

Art hung up where the left window is would look nice, potted plants by the house where the brick is, and a throw in a pattern would look nice as well.