For the vinaigrette dressing: Mix together the grapeseed oil, olive oil, agave, garlic, oregano, parsley, rosemary, thyme, cayenne and lemon juice in a small bowl. Season with salt and pepper. Set aside.
For the mixed green salad: In a large bowl, combine the mixed greens, arugula, red onions, blue cheese, Cheddar, mozzarella and tomatoes. Drizzle with the vinaigrette and toss. Season with salt and pepper.