Not quite as simple as just picking an angle and going with it, but you will probably have anywhere from 2 to 12 degrees to choose from.
The piece of information you have left out is what avg WS you are working with and what speed in rpm you desire which is dictated by TSR which then determines the AOA.
Once you know the AOA, then the pitch angle you desire is defined.
BTW, there are simplier blade profiles than Bergey's to build that would perform equally as well ie flat bottom like the ones used on all Jacobs:
http://www.ae.uiuc.edu/m-selig/ads/afplots/usnps4.gif
from another thread, I have posted the performance data for the above Jacobs blade:
http://www.otherpower.com/images/scimages/7526/usnps4polar.txt
first column is AOA and max Lift/Drag on left is the key data column (higher is better)
I have created a handy Excel calculator for above variables , send me an email if you want it.
Stew Corman from sunny Endicott
scorman@stny.rr.com