I followed the directions in the book except that I only used ginger.
All the fruits are optional and used for different recipes.
I've made wild blackraspberry mead before. If you use a dry (not sweet) yeast the beeries and mead will not be sweet. I would not recommend using more than 3 lbs of the fresh stuff. At 4 and above the mead gets a fruit meaty (thick and heavy) mouthfeel.