I'm not fond of the pressure that wide grip Pull-ups put on the entire shoulder girdle. Through the years I've seen many injuries from those who have chosen wide grip Pull-ups as their primary lat movement.
Granted everyone brings different mechanical advantages and disadvantages to the gym.
However, I'm also not convinced that wide grip Pull-ups builds the lats better than a medium grip.
It might be variety that you need!
Medium grip Pull-ups.
T-Bar Row (A great movement for lat development-highly underrated).
One arm dumbbell rows.
It's hard to imagine not getting the developement that you desire if you are doing three sets of each of the above three times per week.