Heat the oven to 350°F. Heat 2 Tbs. of the oil in a large skillet until moderately hot. Add the red onion and cook over moderate heat, stirring occasionally until soft, about 5 minutes. Add the kale and cook, stirring often, until wilted and tender, 5 to 7 minutes. Season with a little salt and pepper and set aside.
In a medium bowl, combine the onion and kale with the orzo, lemon zest, lemon juice, feta cheese, oregano, thyme, parsley, and olives. Toss gently until combined and season with salt and pepper.
Slice off the top 1/2 inch of each pepper and reserve. With a paring knife, cut away the ribs and discard. Turn the pepper upside down and pat it to get all the seeds to fall out. Divide the orzo filling among the peppers. Replace the top of each pepper.
A red pepper is practically ready-made for stuffing. Just trim away ribs and shake out seeds. Look for pretty peppers with relatively flat bottoms so they stay upright as they bake.
Put the peppers in a medium baking dish and sprinkle them with the remaining 2 Tbs. olive oil and season wtih salt and pepper. Pour the wine in the pan. Bake until the peppers are very tender and slightly blackened on top, about 1-1/2 hours.