If you want to render really good, then learn about mental ray, learn about how to set it up in AutoCad and use AutoCad. AND the underlying method of modelling is a whole different story, which is not actually meant for engineering or architecture. BUT not only do they offer more flexibility, but they are much more complex to use. In fact, the only applications I know, which offer more flexibility and control of the rendering process are 3ds max and maya when it comes to mental ray (or even blender if you're going for "cycles" or whatever their render engine is called). YES, PhotoView360 is set up in a way suitable for loads of engineering purposes, BUT once you want to dive into architecture or similar it is pretty much useless, since it does not offer the individual flexibility you simply need for presentable results. Nonetheless you will create mind-boggling results in AutoCad once you DO know what you're doing. And YES, there are certain limitations to the flexibility of different shaders in AutoCad. YES, mental ray in AutoCad is "pre-set-up" in a great way, so don't bother trying to understand every single variable to the vast variety of shaders, because you will not be able to affect those directly in AutoCad. The list goes on for a while, so: get informed! THEN you will know how you are able to simplify your geometry, use the right type of material instead and let the render engine do the magic. THEN you will know how to control shadows properly. THEN you will know about how to control the number of "bounces" of indirect lighting and how they part into reflection and refraction. THEN you will know about photon emission and appropriate radius settings. THEN you will know about sampling settings to produce the finest edges instead of coarse lines. THEN you will know about portal light and other very cool stuff. THEN you will know about setting up the (very versatile) different types of lights. THEN you will know about caustics and such. THEN you will know about setting up your materials right in order to get the right bump-mapping, relief-patterns, cutout-patterns, transparency, translucency, reflections and refractions, self-illumination and so on and so forth. THEN you will know how to produce the difference between thin-walled glass objects or solid glass objects. THEN you know about things like "ambient occlusion", "final gather", "global illumination" and so many more shader types and stuff, which are implemented into AutoCad in a really useful way.
Search the nVidia site for mental ray to learn more! I highly recommend this. There is mental ray in AutoCad as well! Same render engine used by SolidWorks and Inventor for instance and of course most of the CGI movies like Toy Story or such. Never rely on the predefined render quality settings. Ever fiddled around with the advanced render settings? Guess not. Well actually, if you know what you're doing, rendering in AutoCad gives you similar or even better results than PhotoView360 or something.