Reasonable advocates for greater gun control aren’t looking for “totalitarian” control.

Not according to the legislation they've been attempting recently. It's almost always something that is too far, or just a feature ban.

Accountability is the big one in my opinion. If you own a gun and keep it loaded and unsecured and it is stolen and used to harm or kill others you should bear responsibility, even if it was reported stolen

Define unsecured. This is too subjective, to some it means on your person or locked in a house, to some it means stored in a safe with the ammo in another safe (neither of which I'll have time to open in a break in).

There is often such focus on individual freedom

Good.

individual responsibility falls by the wayside.

Individual responsibility would have the theif be responsible for the theft, not the victim for "being too easy to steal from." You don't actually want individual responsibility to take a front seat, you want to pawn it off on people you feel were culpable for being victimized.

Responsible, legal gun owners shouldn’t be impacted by greater accountability. They would be inconvenienced

You contradict yourself.

waiting periods and more thorough checks.

Waiting periods have shown to have a negligable effect on crime. It is specifically for "crimes of passion," and "suicide prevention," but typically those will be commited regardless with whatever is on hand or they'll just wait the 10 days if they're really intent on going through with it, and if they don't this time they can pick it up and just have it for next time. Mass shootings fall outside the purview of waiting periods, those psychos plan their attacks for months.

"More thorough checks" is also subjective and often how we get into ableist conversations on how "the 'mentally ill' catagorically do not deserve rights." I'm not typically for them. If we actually enforced the laws we already have too that'd be a good start but we can't even do that.

mental evaluation and 1 year waiting period

Ah, yeah, that ableism. Not into it. Which mental illnesses should preclude one from their rights, pray tell? And a murderer one year a murderer the next, they'll bide their time. In fact statistically the ATF says average "time to crime," (that is, time from purchase at a store until it shows up at a crime scene) is *11 years."

And that still doesn't address the 600,000,000+ guns and trillions of rounds already unregistered.