IMO the model should be,
Title and insure all firearms so that even private sales will have to go through at least one government official to run a background check,
Require secure and separate storage of the gun and ammunition verified randomly at least once a year, subsidize the locker though so it's not just a barrier to ownership for the poor,
Require separate licenses for different loading actions and holding classes (one vs two handed),
Provide a permanent office that facilitates both buybacks and also display rendering for folks who just want to keep a hand-me-down for show,
Have a class of criminal and felony law related to the firearm titled to you being used in the committing of a crime or being found in someone else's hands without you having reported it stolen, especially if it can be proven that you handed them the weapon willingly,
Subsidize gun stores being able to build ranges so that people can get their itch out by renting for a day to shoot at targets since let's face it most people buying guns are doing it because they're enthusiasts who'll probably test fire it once and then barely use it again except to pose with it,
Immediately seize firearms owned by someone who is a suspect of a violent crime,
Subsidize replacing firearms for people who were wrongly suspected or convicted of a crime which got their weapons seized,
Prohibit bringing the guns into public spaces aside from hunting grounds and shooting clubs and events,
Post federal security at the entrances to gun shows and shooting events to detain anyone who'd fail the background check that's trying to get entry.