Tara Ella has written a piece, "Why This Liberal Couldn't Support Bernie Sanders or Jeremy Corbyn." It isn't very much about either Sanders or Corbyn; it's mostly a philosophical treatise from a self-described liberal who offers a preference for "smaller government." Some of my thoughts:
A lot of readers are going to look on your talk of preferring "smaller government" on rather vague "moral libertarian" grounds as allowing ideology to overrule reason. And they'd be right to do so. You don't actually engage with the arguments for the policies you're dismissing here, arguments that are much more practical than, as you seem to suggest, ideological.
The growing opposition to private health insurance, for example, doesn't flow from some ideological commitment to abstract socialism; it comes from entirely pragmatic considerations. Insurers don't add anything to patient care. They're just a middleman, and their rapacious pursuit of profit leaves huge numbers of people without any coverage, even larger numbers of people who theoretically have coverage without care or with constant bureaucratic intrusions into their care and it jacks into the stratosphere the price of care for everyone. One could perhaps do better with some theoretical public-private hybrid--it would be almost impossible to do worse--but any private involvement has to feature that profit motive, and it's just not a necessary expense.
You don't engage with any of this, and all you place against it is that ideological preference for "the smallest government method to achieve the aim…"
As another example, you write that "heavily restricting free trade is a retrograde policy that was discredited back in the 1970s," but this not only fails to engage with the objections to what is misleadingly called "free trade," it actively distorts them. The multilateral "free trade" deals to which progressives object have very little to do with trade. They're about granting legal superpowers to multinationals, establishing institutions that, among other things, allow them to collectively challenge democratically-enacted regulatory regimes and mete out economic punishment to nation-states that fail to fall in line. And falling in line means a race to the bottom for peoples everywhere in the name of profit by the few. Opposition to this is not, as you suggest, just long-out-of-date reactionary protectionism. Since you've expressed your preference for lesser government, it's also worth noting that these "free trade" agreements are, themselves, a major government intervention into economic activity, and are also protectionist (all of them extend new monopoly protections, for example, to "intellectual property"). It's just that it's carried out on behalf of these multinationals.
Now obviously, your article isn't about healthcare or this sort of "free trade" and it would be unreasonable to expect some sort of detailed discussion of every general issue you raise. What I'm describing is the impression you're giving by how you do deal with them.
When you discuss moral agency, you write that you believe "all individuals should have maximum liberty over their own lives" and that "a government that is too big is incompatible with this aim." But here, again, the issues you've raised beg questions regarding the application of this notion, questions you fail to address. Our experience with for-profit healthcare is that it utterly decimates large swathes of the population; all it takes is one injury or illness and that for-profit system can swoop in and take away everything one has, everything for which one has ever worked, completely destroying one's independence and one's opportunities in life. There's not much "liberty" left for someone in that fix. When the government facilitates the mass-export of jobs, that not only harms individuals, it devastates entire communities. This "maximum liberty" thing is a lot more complicated than you've treated it here; there's certainly much more to it than just some abstraction about the size of a government.
You ask a few questions that effectively critique elements of liberal democracy and, of course, that could be developed even further. Entrenched interests do exert undue influence over it, political representation usually isn't so great and politicians' actions frequently don't conform to public opinion--it's an extremely flawed system, arguably critically flawed. Still, the basic principle at the heart of democracy is self-determination, which is, of course, one of the most basic and indispensable principles of liberty. The liberal democracies are imperfect but they're an effort to apply this principle to a state system. Returning, in light of this, to one of those particular issues you raise, the push for single-payer healthcare is a democratic one. Advocates of the policy have been organizing, making their case for their preferred policy, supporting politicians who promise to enact it and so on. You write that the only way to preserve liberty is by limiting the size of government but that presents an obvious problem if the democratic consensus is opposed to that sort of limitation on government. That's a limitation on one principle of liberty. It may further others but again, that's an argument that must be made. You haven't made it, and your flat declaration that limiting government is the only path fails to acknowledge that the conflict exists.
Just some thoughts I had while reading your piece.