Good architectural visualisation is essential of conveying your intensions and ideas through the design or marketing processes. In my opinion, the basic aspects of a rendering should consist:-1.A Strong Message
What is the intension of the image? What is the idea you are selling?
Is it the surrounding context with integrated architectural solution?
The form or detailing of your façade you want to illustrate?
The atmosphere or activities of the design created?2. The Depth
The background with a sense of depth, the foreground with simple detailing and the million dollars building should be a basic composition of an image. A gradient, some clouds or buildings as background, some silhouettes, and plantings as foreground will do the job. A sense of dimension should exist.3. The Color and Texture
The mood and feel of the rendering is like a potion of love of an illustration.4. The Light and Shadow
Without any color and texture, the light and shadow of an image can construct a sense of depth, a sense of material and even the mood of an image. How you direct your light is as if how you convey your message.5. The Eye flow
The composition and structuring of your content in an image shall paragraph your ideas in sequence, allowing your audience to read your ideas clearly with comfort. I suppose this to be done intentionally. Study your image after the image is completely. A final touch or checking helps a lot. Ask for opinions even.