1. Universal registration including serial numbers. Penalties for illegal possession, including if someone else uses your gun, should be massive. Penalties for possession of a gun without serial numbers should be huge.
2. Insurance and licensing. Owning a gun should require a license. Possession without a license for the registered gin should be a felony.
3. Restriction of weapons able to kill people. All rapid fire weapons, including hand guns, should be limited to supervised use .. gun ranges, designated hunting areas.
And, of course, a tax to cover the costs of this.
It needs to be recognized that urban and rural areas need different gun rules. Many people in rural areas keep guns for protection because the police may be an hour or more away. Cities should be able to regulate guns more strictly. There is no legitimate reason for civilians to possess machineguns, therefore bump stocks and similar devices should be banned. Ultimately, technology — e.g. trigger mechanisms that allow only the gun owner to fire the weapon — may prove to be our salvation from rampant gun violence.
Strict gun reogistration would help the cities wiht no harm to the rural areas