Slice each egg in half and transfer the yolks to a mixing bowl.Stir in 2 tablespoons mayo, mustard, onion powder, garlic powder, pimentos, and pickle relish. Add the remaining tablespoon of mayo if it seems too thick. Fold in cheddar cheese and most of the bacon. Season with salt and pepper to taste. Spoon into the egg whites and sprinkle with bacon and pimentos, if desired.