I have been waiting to see if anyone can send you photos of their verandas, but as they have not I will add a few comments.
There are many ways to build these columns, and some look better than others. The columns that are detailed are large, and you can certainly reduce the width of them by 6-8" and still have a well porportioned columned. The main thing is to keep the taper at a similar slope,as any more will tend to look odd. If you want us to show you what it would like like smaller I can send you a drawing.
Meanwhile, others should still send links to their completed homes