7) If there is complete degeneracy (no matches among any given species), consider using the base inosine (structurally similar to guanine) as it can pair with any of the four bases, although it will bind to cytosine preferentially. Alternatively, insert N for aNy base to ensure equimolar concentrations of each base at that position in your primer mix.
8) Avoid degeneracy at the 3’ terminus (this would not be a good place to insert inosine).