my understanding is that wings are the perfect combo of meat, fat and bones (calcium), not sure why u think here isnt sufficient meat on them. my hound has around 14 daily (10 in the evening and 4 in the morning) and is in great condition. he weighs in at 32 kgs
cant really see your dog as its lying down ,but from pics looks in good nick, i have been feeding mine chicken wings for 2 years and they do well on them ,but allways looking for way to get dogs in better condition, so all up how much in weight you giving him?