Consider the ramifications: with voluntarism as nearly the only requirement, libertarianism is a substrate for communities to layer additional rules on top as befit their values: socialist communes, gun-free zones, drug markets, shared libraries, required weapons training, a Greek-style local democracy, whatever. Two communities can be diametrically opposed in their values, sharing only the common tenet that everyone participates voluntarily.
Of course it's impossible to pull off: can kids born in each community be considered voluntary participants? Can someone revoke their rights for the rest of their life with the stroke of a pen? How does someone traveling through these places even keep track of the laws (we see this with states already)? Lots of difficult/impossible/senseless questions arise. But it's a thought experiment: absent religious considerations, is there a more moral system that allowing everyone to voluntarily interact with others in only those ways that are mutually beneficial?
Those details aside, if allowing as many people to craft their life experiences as voluntarily as possible is of merit, investing great power in a central power governing over 300 million people is an extremely poor way to achieve it.
Please show an excerpt where I imply that my morals are relevant to your opinions.
When I say 'I have a moral problem with your willingness to "force" someone to do something' I mean 'I can refute it on moral grounds'. The refutation being, forcing someone/a monopoly/a group of people/a corporation to act against its incentives is perverse (it minimizes freedom) and especially so when there are alternatives that are not perverse and that maximize freedom, which is competition.
I think you're overcomplicating this.