Slice 2 eggplants 1/2 inch thick; lay on paper towels, sprinkle with salt and let sit 10 minutes, then pat dry. Heat 1/4 cup olive oil with 1 grated garlic clove in a saucepan, 1 minute. Stir in 1 tablespoon each chopped oregano and parsley, 1 teaspoon chopped rosemary and 1/4 teaspoon red pepper flakes. Let cool; pour over 4 ounces crumbled feta. Brush the eggplant with olive oil; grill over medium-high heat, 5 minutes per side. Top with the feta.