This might take a little practice to get the hang of it but the results will be worth using less weight. To work the deadlift, perform deadlifts off the block to the exclusion of regular deadlifts. Stand on a sturdy platform or plate that allows a little extra range of movement while not letting the bar crush your feet at the lowest position, perhaps about 2-3 inches high. This exercise really develops the pull from the floor. Even if the start of your deadlift is strong, the extra power developed will help the bar to be pulled past any sticking point higher up due to the velocity of the bar.
Shrugs are the top pick for lockout power.
Be sure to get a full range of motion, pulling up to your ears and hold it for a count and then lower. Relax the arms and let your traps to the lifting. Lifting straps are invaluable here so don't limit your shrugs in an attempt to strengthen your grip. You can not overlook the importance of strong abs for powerlifting. Ab crunches can be done 2-4 times per week for best results.