Hi Edouardo,
I too am new to arch viz and i hope i can help with your scene.
I would first consider the exposure of your scene. to me it seems a little over exposed. this would be washing the colour from. Its hard to say without seeing you camera's setting but i would look into Changing the shutter speed.
Another thing i would consider would be the position of your sun. Photographers rarely include the sun in their images. place the sun behind the camera and not in the shot.
Checking you materials couldn't hurt either. It seems to be a block colour rather than a material with any real world properties such as texture and reflectivity. Your material, to me, seems way too reflective.
Some extra consideration i would add would include the composition of your image. The photographer has clearly used the rule of 3rds (give it a google. Its real simple to incorporate). You could include some clouds?
Dont get lost in the simplicity of this photo. Although it may seem simple at first glance there is a lot of complexity within in the scene. Aerials, Windows ect. Teir is also some wear to the builing and extruding bit which stop it from being simply 2 cubes.
You're right in saying this is a really cool style.
Its a really nice start and i really like this style and may consider it myself.
As i said, i am no expert myself, so take this information at face value and let me know how you get on.
Adam