Correctly conceived, the purpose of ethics is to provide an objective means for the peaceful resolution of all potential conflict over scarce resources. Ethics achieves this by identifying those objective rules that are consistent both with the logic of argumentation and with the limits set by reality.
The only ideal that underpins this ethical system is the desirability of peace itself. Therefore, this is is the only ideal that libertarians need to agree on. All other goals that have been associated with libertarianism are merely a consequence of this single ideal and are not fundamental.
The popular idea that libertarianism is fundamentally about the ideal of individual freedom is therefore misconceived. Individual freedom is a consequence of the ethical system that requires respect for ownership of one's body and of other rivalrous objects. The goal is the peace created by objective property rights. Individual liberty is the effect of that goal's successful implementation.
Similarly, economic prosperity is not a goal of libertarianism, correctly conceived. One could be an ascetic who is entirely uninterested in prosperity and still be a libertarian in good standing. Empirically, it happens to be the case that people tend to enjoy prosperity and so, if left in peace, they will create it. But this is an empirical consequence of implementing the ideal of peace– a different ideal to prosperity.
Another ideal that is sometimes ascribed to libertarianism is the goal of eliminating deference, hierarchy, and tradition. This may reflect the historical origins of libertarianism in the Enlightenment, which challenged certain traditions and hierarchies of the time which were inconsistent with objective property rights founded in rational argument. However, there is no inherent incompatibility between objective property rights and the existence of deference, hierarchy, or tradition. It depends on the specific social practices and institutions. Those that violate objective property rights are incompatible with libertarianism, but those that do not are compatible with it.
Lastly, the ideal of the pursuit of happiness has often been ascribed to libertarianism. Although the actions of every individual can ultimately be said to be in pursuit of his or her happiness, this is irrelevant to the problem of ethics. When we are concerned with how to avoid conflict over scarce resources, we are asking how to determine who should have rightful control of each scarce thing. The pursuit of happiness doesn't come into it. You achieve peaceful coexistence with others by mutual respect for property rights. Whether or not everyone is happy is their own business.
The implications of this understanding is that libertarians should always focus first on those issues that concern challenges to peace. That is why opposition to war, or noninterventionism, is the most important cause for libertarians when it comes to international issues. Closer to home, opposing any challenge to peaceful enjoyment of property rights should be the focus for libertarians– whether that is from the State through taxes or government edicts, or from private criminals through violent crime, property crime, civil disorder, rioting, and so on.