I Am Not a Libertarian but a few thoughts come to mind. Bitcoin is just about as close to the libertarian ideal as you can practically get in this world. The two main flaws that I can see is that it's not as anonymous as it could be, and many governments have already imposed a number of burdensome regulations which prevent people from using bitcoin as they see fit. More anonymity would get around those regulations to some extent (not saying that I agree with doing that, it's just the pedestrian reality).

WRT most of the wealth being held by a small number of people, I think it's inevitable that power structures like this arise in human societies. If you leave things unchecked, some people will acquire way more wealth than others. Doing away with regulations will likely only make that worse, not better. I'm more of a socialist, so I would prefer that we somehow limit the amount of wealth that a single individual can hold, because it gives them a tremendously unfair amount of control over the destiny of humanity as a whole.