The house is fairly small from the photo but elevated on a basement or garage plinth. If the base is brick, leave it as is. But whatever colour you chose, eliminate contrasts so if, say, a soft French grey, paint the walls, window and door joinery and roof flashing the same colour. A contract could be the new deck rail, but I would even consider painting it the same colour as the basement to link the 2 levels or just the same as the top. A bright glossy front door could break up the monotone.

How about a more contemporary wire rail system as shown below. Also a lovely green grey upstairs may work. The one below is Taubman's battle green full strength - computer colour of it is not accurate.

This is the inside of the house. The bottom photo is the inside of that extension. The House is a Yellowy Creamy colour that is very dated and we want to change to a more neutral off white at a later date. I did think that a white or off white for the outside might look a bit too white and washed out with the white Brick. The Brick does have like charcoal flecks through it. So maybe that colour could be good to coordinate with.

There are tonnes of colours to choose. Take a sample pot of Woodland Grey and a sample pot of Surfmist and mix up your own custom colour guaranteed to work with your chosen roof and trims.