Heat oven to 425°F. Bring a large pot of salted water to a boil. Cook asparagus, in batches, until crisp-tender, 3 to 4 minutes. Run batches under cold water to cool; pat dry. Whisk together lemon zest and juice, 3 tablespoons oil, 2 teaspoons thyme, and 2 teaspoons honey in a bowl. Season with salt and pepper. Place feta in the center of a large piece of aluminum foil. Drizzle with remaining teaspoon oil, remaining teaspoon thyme, and remaining teaspoon honey. Season with salt and pepper. Pull the foil up around the feta to create a pouch. Bake until warmed through, 14 to 16 minutes. Drain excess liquid and crumble with two forks. Toss together snap peas, radishes, cooked asparagus, and vinaigrette. Serve immediately topped with warm feta.