Stephen Strange has always been more about intelligence than brute strength. Strange wins by out-thinking his opponents rather than out-zapping them, which is part of what made the Lee/Ditko run remarkable. He can pack a punch when necessary, both physically and magically. Mordo creates a whole cult to seek down his archfoe in Strange Tales #130 and 131. They get a nasty surprise when they approach him from behind before he can cast a spell: Stephen's magical training includes martial arts. They are really potent. Defenders #9 demonstrated that Strange is more than just skilled. He can compete with Mantis, who is among the finest Marvel martial artists.