Great advice so far in this thread. For grip strength I would focus on any type of thick bar work as a staple and the rope or towel pullups fit the bill for this. Also strong wrists help when someone is trying to get out of your grip so sledge hammer levering all directions are great for this. Also when someone pulls out of your grip alot of times the thumb is the weak link. Plate pinches help with this. Defranco has a good grip routine that is done 5xwk on his site under the question and answer section. Hope this helps and feel free to ask any questions you might have. Keep up the good work!