Well. When the space is deep enough there’s a point where there’s no more light getting inside, and balancing natural light with artificial is always tricky. Right now the only hdri set I’m using is the one from 3dcollective.com, which is really well produced, all the skies with the correct dynamic range to naturally light environments.
In this case I used one of their hdris so the sky would look somewhat cloudy, I added a corona sun with the kelvin temperature modified to something like 6000k, bigger size, low intensity, and also cheated a bit with a rectangular light just outside the balcony adding some extra fill. It’s especially hard when the diffuse value of your materials is low, they don’t bounce a lot of light. The rest are the artificial lights themselves, which are just spheres or cylinder lights in a warm temperature and low value.
Although I did make a rookie mistake here and did not align the hdri sun with the corona sun correctly, it’s mildly noticeable in the overhead view, the chair is casting shadows to the left while the sunlight is coming in from the top left.
When I get a chance at home I’ll take some screenshots of the lighting setup
