After a little more experimentation and some internal debate,  I decided to go with Antarans suggestion.  My primary problem has been that Carrara doesn't develop very good trunks for certain kinds of trees and C can't do what I've read about classified as "hero" trees.

Even simple branch distributions for pine trees don't really work out very well in the plant editor.

So, I figured building my trees using Antarans suggestion is a really good thing to try.

I am on a business trip but when I get back, I will let you know How it goes.

-Kix