pullups are a good measure of your power to strength ratio. They do not neccessarily represent how you strong you really are. As mentioned above, some can do no pullups but can out lift in back exercises with weights. if you can't reach 15 pullups, you are not developing your body strength in a balanced manner. Core exercises include, pullups, pushups, and squats. You'll need to do more of these to help develop undereveloped support muscles. Reducing your bodyfat will also increase your pullup count and ultimately your power to weight ratio. P/W: is key in fighting.
oh yea, my max ratio was 22 pullups at 215lbs 6'2". Pushups, i dont even know, but i am 60+ in one minute.