Heller is not important alone, because the terms in Heller are undefined. They can still be defined by either the antis or the pro-rights side in court.
"Reasonable restrictions" means whatever is deemed reasonable. Gun control in the UK is 'reasonable' to the population there.
In fact Heller gave credibility to firearm restrictions in ways that are unprecedented by acknowledging restrictions and prohibitions as unchallenged by the ruling.
Miller even raised the challenge that prohibitions on military arms, the type useful for any militia purposes was illegal. The court itself essentialy made that argument. That the only reason they ruled against Miller (who was dead and nobody argued on his behalf) was nobody could present evidence that a short barreled shotgun was a suitable military arm.
If it had been a full auto machinegun in question the court's logic would have ruled it was illegal to ban.
So Heller has legitimized gun restrictions that are so severe as to be defacto bans.
At the same time it has acknowledged the military purpose of arms protected by the constitution, and so opened the door to challenges against such arms.
Heller basicly just undid most protections (which were already being ignored) as well as left the legality of new restrictions undefined.
A blank piece of paper, that is still to be determined in the lower courts.
Arguably that is a defeat for us as gun owners. We already had our rights, supposedly protected by the constitution. Antis already claim they are not trying to ban all guns, just impose new endless "reasonable restrictions". Restrictions on type of firearms, types of actions, types of cosmetic appearances, taxes to save the children, taxes on every round to pay some expenses, waiting periods, increased waiting periods, licensing, registration, fees, etc etc
Every time they are successful the percentage of new gun owners goes down.
Which is the whole point, to price the cost, and the time consuming hassle out of the willing reach of a larger and larger segment of society.
The fewer gun owners, the weaker the opposition to additional legislation.
So Heller is not really a win. It is only a win in that it says an absolute ban is illegal. Yet it does not outlaw a NYC style ban, which is not itself a ban, just a licensing process most normal people cannot pass. Yet unless someone is actualy responded to, and turned down, they do not have standing to sue.
Further Heller legitimized licensing and registration. It in fact ordered that DC allow Heller to register his firearms.
We all know registration leads to various forms of confiscation and emboldened restrictions, as it has in most other nations.
So most of the things that could be positives in Heller are yet to be defined. They can be defined for or against us.
Most of the negative things that already existed, have simply been ruled to actualy be constitutional.
So Heller could end up being more of a loss than a win.
Registration, waiting periods, fines, licensing, permanent denial of the right for legal offenses, the NFA, Hughes Amendments etc have all been ruled constitutional by Heller.
So most of us gained nothing, unless you lived in DC or Chicago. Most of us did lose a lot. The question of whether many current restrictions, even restrictions only the most restrictive places even have implemented are legal was answered: Yes they are legal, if they are "Reasonable".
So many places reluctant to impose various requirements like registration can now proceed knowing licensing and registration is entirely constitutional.
Other terms in addition to "reasonable restriction" is anti gems like "unusual and dangerous".
Ray guns and phasers have been outlawed now before they are available. In all seriousness, the people have henceforth been forbidden from progressing with technology to new arms.
So if the military was to solve the powerplant issue and move on to portable rail guns, and various rays, they would be "unsusual and dangerous". They would also not be "in common use".
The "in common use" clause is really interesting. What comes first, the technology and use, or the ban that prevents common possession? Essentialy anything outlawed early is never in common use, and is unusual and dangerous.
The military is now using acoustic devices to make people nauseous and sick. Devices to disorient people and make them dizzy with radio waves through walls, so they cannot fight as well.
Devices like the Active Denial System which causes intense heat and pain with microwaves.
http://www.defense-update.com/products/a/ads.htm
There is lights designed to just make people sick:
http://www.foxnews.com/story/0,2933,292271,00.html
There is other light and sound weapons with a variety of effects.
Frequencies that damage or destroy most unshielded electronics can be used.
https://acc.dau.mil/CommunityBrowser.aspx?id=146923
I could go on and on about new, and old less known technology used as weapons.
Nevermind things still classified citizens will learn about as they are used against them and others.
Some of these technologies can also be altered to become lethal tools. Future weapons of sweeping lethal beams is a reality.
Ray guns are a future reality.
In a future where much of the government possesses such things, they would still be "unusual and dangerous" and not "in common use" for the average peasant.
Things are changing rapidly, yet Heller allows all of it to forever be banned from use by regular citizens.
So no, you are right to be concerned. Heller legitimized many anti gun positions, and anti gun methods. The few things that could be positive have yet to be defined in ways that are positive through court cases.
So the only "good things" are not yet defined, meaning they are not even "good things" yet. So we got a lot of bad, and a few undefined "good".
The only defined thing is a complete and total absolute ban on handguns is not legal. However a very difficult restrictive process that significantly discourges most of the population, has long waiting periods, loses the applications regularly, expensive fees, allows x type of guns, y capacity...
So even that is just barely a partial win even in the couple cities it impacts.