More than 520 people have died in U.S. auto racing in past 25 years. Two of every three deaths in U.S. auto racing over the past three years occurred at short tracks, which have been slow to embrace changes that are saving lives in racing's major leagues. https://www.charlotteobserver.com/sports/nascar-auto-racing/thatsracin/article9152399.html The Centers for Disease Control report that here in the United States, on average, 3,536 people died from drowning annually from 2005 to 2014, which equates to 10 deaths each day. Then there are the thousands of others who suffer swimming pool-related injuries each year. https://www.edgarsnyder.com/statistics/swimming-pool-statistics.html
Better hydration tests, less rounds. Rounds are the last part of the sport not accounted for safety. If we figure out the closest to the safest amount of rounds that wouldn't allow for death to occur, then we should give it a shot. It's up in the air though, maybe 10-12 is alright. It's often found that dehydration plays a strong role in these deaths.
The way the sport is you cannot do much more. It is a matter of catching any sort of bleeding before it happens, and hindsight is always 20/20.. If you change the sport too much you don't have boxing the way we know it. Headgear? Bigger gloves etc. I don't know. Maybe try and discourage courageous cornermen. It is a sport so if a fighter is being hurt and hit too much stop the fight and have him fight again another day.