Heller was the "Court's first in-depth examination of the Second Amendment, one should not expect it to clarify the entire field". Using the terms "unaltered" and "unchanging" are not really appropriate. Heller specifically mentions that "we do not interpret constitutional rights that way." We are to use the understanding of the right at the time of the founding to address modern issues. The Court wrote Caetano because the MA Court did not change the right to address modern issues.
The hard part is trying to correctly understand what the right actually meant. Was concealed carry prohibited because it was something only criminals would be inclined to do or was it prohibited because it was considered unusual or uncommon in society. The former interpretation would lead to two possible outcomes, the latter would suggest other possible outcomes.
In today's society open carry can provoke hysterical reactions from the public. Norman did not base their decision solely on the fact that the right is not unlimited. They invoked intermediate scrutiny to justify their decision based on compelling government interests.
The reason that Heller would have lost the permit argument is because the Court does allow certain restrictions such as permits as long as they are reasonable for the circumstances.
From what I can tell of the antebellum cases it was always referenced that concealed carry was some kind of a scourge on society, and a ban on it was basically a crime reducing measure. Several factors come into play however. The cheap pocket pistols were always attributed to poor and minorities and were thus relegated to gangbanger instruments with no constitutional protections.
We're quite a ways off from that in today's society. Not only as mentioned above all states allow for CC (and in some cases ONLY CC), but we now have a system where individuals are able to walk around but still be prohibited from owning (and obviously carrying) arms. So society is more concerned now with WHO is carrying rather than HOW they're carrying, whereas the opposite was true in the 1800's.
Everything today points toward allowing CC as a viable, constitutionally protected mode of carry. The only issue against it is that yes, criminals will continue to only carry concealed. However even the good guys by and large will want to CC over open carry, so a "thieves veto" shouldn't be allowed to stand.
As for the permit requirement I agree basically because the court is in no way ready for that yet. A bit further down the road after some more positive caselaw this can be successfully tackled.