Yes, all arms are covered by the Second Amendment, not just "standard military issue". A tank would contribute to "the preservation or efficiency of a well regulated militia", so would a MG or nuke.
The clause in the Constitution providing for Letters of Marque basically gives Congress the power to hire privateers to act on behalf of the country. This necessarily implies that the privateers have better weapons than mere rifles, MG's, etc. Back in the 1700's, such people had ships with cannon, which would suggest that in the present day they would have destroyers,cruisers, etc. with missiles, gatling guns, helicopters, etc. I would suppose that this would apply to tanks (the equivalent of armored cavalry) and planes (no equivalent but so what - there was no equivalent to computers and the Internet, and the 1st Amendment still applies to limit government censorship). Of course, were someone to abuse their right to keep and bear a tank, for example, then he or she could expect to have some other citizen (or group of us) with tanks or fighters to take it (and likely his life) away. This would be similar in nature to penalties for abusing the right of freedom of speech (slander is punishable, as is shouting "fire!" in a crowded theater
when there is, in fact, no fire)
I draw the line at nukes or other WMDs, because these are area weapons (i.e. indiscriminate in their action). All other weapons can be utilized with a degree of precision (if the user is skilled, same as with a rifle), but WMDs are different. Of course, one can say that since the government derives its power from individual citizens, it cannot have more power than any one individual, but I can't buy into that. That would be anarchy, or at least a tyranny of the minority (no better than any other kind of tyranny). In any case, I'm not holding out for my suitcase nuke - right now, I'd be quite satisfied if the '34, '68, '86 and assorted Clinton-era gun control acts disappeared. In fact, we best not waste any effort on more than these unconstitutional acts, as such effort will be totally wasted efforts and will take away from what might be accomplished with a concerted effort over time.