Various Second Amendment issues are already being decided by the lower courts:
Steven Skoien has two convictions for “misdemeanor crime[s] of domestic violence” and therefore is forbidden to carry firearms in or affecting interstate commerce. 18 U.S.C. §922(g)(9). Wisconsin informed Skoien about this rule; he signed an acknowledgment of the firearms disability.
The provision was upheld by a 2-1 vote, the dissent wishing to remand the issue to the district court basically for more factual analysis and a determination if non-felons are truly not protected. The majority held that this statute fit within one of the exceptions cited by the Supreme Court in Heller as a type of provision that the ruling should not be assumed to override. That is, gun ownership by those convicted of a crime, or more specifically, a class of people specifically likely to cause "armed mayhem." Cf. Martha Stewart with this offender.
Heller's citation of "felons" and other categories in conclusionary dicta however doesn't conclusively decide the issue. And, the number of non-violent felonies alone suggest some need for clarity. Should some tax offender be denied the right to have a firearm at home for self defense? OTOH, released felons are denied voting and other rights, including having less privacy from home visits and so forth. How about someone who was in some sort of mental institution some time back for some eating disorder? Are they now mentally ill and able to be denied a right to own a firearm? What should be the basis of determining such things?
For the category where limitations were left open, factual data is relevant:
Both logic and data establish a substantial relation between §922(g)(9) and this objective.
And, the ruling cited such data. The dissent accepted that up to a point, except where the 2A categorically bars that -- for instance, if non-felons are protected, the choice is made constitutionally, not by use of scientific data. One problem, inviting some questionable rulings, is that the Supreme Court did not clarify how the lower courts should rule in this area. A historically commonly accepted firearm at home is one thing, but there are lots of situations where the answer is unclear. As with other areas, the rulings are facially broad, but in many ways quite shallow.
Ditto giving rights to detainees in Gitmo, but leaving to lower courts the power to determine that exactly that means, often without too many people paying much attention.