Whenever possible, add resistance to your ab exercises with weight. Most people increase the load on exercises for major muscle groups but they don't on ab exercises. That's a mistake. Think ankle weights for leg raises or a 45-pound plate for crunches as shown here.
If the bar is slipping out of your hands on the deadlift, your grip isn't strong enough. But since grip strength is mostly neural, it doesn't take long to see drastic improvements if you work on it.
Are black athletes, generally speaking, better than white athletes? Don't get your panties twisted. Instead, take a look at this unbiased, apolitical analysis.