Have you read Peter Reinhart's Whole grain breads; new techniques, extraordinary flavor? All of the recipes in the book use a soaker and a preferment/biga or sourdough starter. The soaker is typically 50% of the flour and 50% of the water and a small amount of salt, well mixed and then left at room temperature overnight or up to 24 hours; refrigerated if longer than 24 hours. The biga is the other 50% flour and 50% water, 1/4 teaspoon instant yeast, well mixed and then put in the fridge at least 8 hours and up to 3 days. For the final dough you combine the soaker and biga, 7 or so tablespoons of whole wheat flour, a wee bit more salt, 1 1/2 teaspoons instant yeast, a little sugar, mix well, knead a bit, then let rise for an hour or so.
It's a very interesting book and fun to read.
He has a whole wheat pizza dough in it; the final percentages are
whole wheat flour: 100%
instant yeast: 1.2%
olive oil: 5.6%
I thought I'd mention it as additional food for thought in your whole wheat pizza dough quests.