Here's my list:
1.) The vast majority of gun deaths come from suicide in the United States. That stems from lack of access to healthcare, including mental health care. Single -payer or medicaid for all helps reduce that. If we truly believe that it's not the gun, but the person using it, then let's give our citizens the ability to get the help they need w/o the stigma associated w/mental health issues. This can be done at the state and national level
2.) Inner city gun violence is largely driven by poverty & a perceived lack of mobility out of impoverished areas. Free college or collegiate investment programs w/civil service payback opportunities, especially to vocational institutions where people can learn trades, would help reduce the perception that violence is the best way out of a bad economic situation while giving people the tools to lift themselves out of poverty. There are programs in states like Wyoming, Kentucky, etc that help achieve these goals with significant success in lifting people at risk due to economic insecurity into a place where they have the opportunity to make a better living.
3.) Economic development in impoverished rural areas: Through various tax incentives & workforce education programs, we can entice employers to move into rural areas which often times have lower costs of living for employees w/higher standards of living. In a digital economy, place doesn't matter so much as your quality of workforce, and remote working is a real thing these days.
4.) Gun violence on reservations is directly attributed to poverty, substance abuse & domestic violence, so having specific programs for Indian healthcare reform, increased access to healthcare & also better educational opportunities in tribal colleges & off-reservation can go a long way towards reducing gun violence, as well as investments in cultural programs that teach young residents about their past and providing economic incentives for native-owned businesses can help reduce gun violence.
5.) Fund & enforce existing laws: NCIS background checks often times lead to no sale for people who trip the trigger, but the follow up isn't necessarily there in terms of contacting the violator & making arrests as needed. We have some very thoughtful approaches to gun laws in the U.S., but we don't always provide the funding to LEO's to enforce them. It's time to do that.