Slice the two zucchini in half lengthwise, then slice them into half-circles about ¼" thick. Dice the bell pepper into ½" squares.
Place sliced zucchini, diced bell pepper, and tomatoes onto a baking sheet. Toss them with one tablespoon of olive oil, sea salt, pepper, oregano, and ½ teaspoon red pepper flakes and toss until all of the vegetables are evenly coated.
Add 3 cloves of unpeeled garlic to the baking dish.
Roast the vegetables and garlic for 15 minutes. Toss the veggies and roast them for 20 minutes more, or until they are golden brown.
While the vegetables are roasting, fill a large pot with water and bring the water to a boil.
Add the orzo and cook it according to the directions on the package.
Carefully peel the roasted garlic. Add the peeled garlic, two tablespoons extra virgin olive oil, water, both the balsamic and white balsamic vinegar, agave, sea salt, and ground pepper to a blender or food processor and blend until smooth.
Add the orzo, roasted vegetables, and vinaigrette to a large bowl and toss until everything is combined.