if the false dichotomy was "either nobody gets guns or everyone gets nukes", i'd choose the latter
in fact, within our lifetimes, people with elon-musk level brains and wealth can have their own nukes if they want them. the US Manhattan project achieved its aims with comparatively primitive tools, compared to what exists today.
That said, I think that the spirit & intent of 2A was that the common man should be as effective as a professional infantry. Therefore, he ought to have the weapons of the professional infantry of his day.
That means, American citizens should be able to own: select fire weapons, grenades, radios, body armor, etc.
That rule of thumb excludes jets, largebore weapons, nukes, etc.
Interestingly, the colonists did have heavy cannons, and, the opening skirmish of the War of American Secession was when the brits marched into a town to try and confiscate the colonists' cannons.
So, the fact that the colonists retained cannons suggests that artillery/tanks/howitzers might be fair game for civilian ownership also...
As a practical matter, i think each town or county should have an armory, with tanks, crew served weapons, and heavy vehicles. The armory should be under the command of state level guard, and constitutionally prevented from ever serving under federal control without express authorization from that state's governor, and constitutional restrictions on ever serving outside of the borders of the state.
(the current National Guard doesn't have either restriction - and it should have both)
Texas has a Texas State Guard that is separate from the NG.