Just had interesting experience of attending a lecture-demonstration by a famed portrait photographer. The set-up used was...two lights. Umbrellas, or soft boxes (read, soft shadows), and featureless backdrops. In one case she substituted a bounce sheet for one of the soft boxes. I can't say I've figured out how to make lush but realistic lighting in Carrara. But I have been doing quite a lot with very few lights. GI (aka indirect lighting reflection in the scene), and Sky Dome both do marvels in getting a smooth coverage across surfaces and softening the shadows. If you haven't already tried this, try some light-lab work; create a test scene, and work with one light at a time to see what that light is doing. Try distant lights, ambience, spots with soft shadows, shape lights, Anything Glows panels (I've used a large Anything Glow panel as a light source several times), Sky Dome, HDRI, et al.