Philosophy

The central tenet of legal realism is that all laws are made by human beings and therefore subject to human imperfections, irrationalities, and frailties. Legal realists shared one or more of the following ideas

Indeterminacy of law. Realists believed that the law cannot determine the actual results of legal disputes. It is possible that a judicial decision may have been determined by extra-judicial factors

Interdisciplinary approaches to law. Realists believed that a psychological, sociological, and anthropological approach to the study of law is necessary in the resolution of legal disputes. An interdisciplinary approach puts more clarity and substance to many legal issues

Legal instrumentalism. This is the belief that the law should be used as an instrument to achieve social progress and balance competing individual or group interests. In short, the law should cater to the needs of the society (and therefore should never be irrationally restrictive).

Proponents of this view advance two broad claims 1) the law is indeterminate, and hence, the judges must often draw on extralegal considerations to resolve disputes presented to them, and 2) the best definition of law is operative definition of political action. In its orthodox sense, the law is the set of rules, regulations, and policies which govern the actions of individuals within or outside the state. Legal realists define law as restraining actions tied intrinsically to real-world outcomes of particular cases. In short, a law is a derived reflection of empirical consideration  whether such empirical consideration is a repetitive or closed event.

Proponents of this view argue that it is not concerned with what the law ought to be but rather to describe what the law is. The law is simply what is ordered by a lawmaker. Judges are not lawgivers and therefore their actions, while belonging to the field of law, are subsumed under legal practice.

Legal Realism vs. Radical Feminism
Radical feminism is a theory which states that society is organized into a set of complex relationships based on an assumption of male superiority. The essential goals of radical feminism are as follows 1) challenge and overthrow the patriarchal system, 2) oppose standard or socially accepted gender roles (oppression of women), and 3) restructuring of the society. In its abstract sense, patriarchy means the consorted dominance of males in the economic, social, and political affairs of the state. It is, in general, the source of all problems in the society. Radical feminism emerged out of the failure of liberal feminism to affect policy changes in the 1960s. Some women viewed liberal feminism as an outgrowth of patriarchy, and as such, a matter for abandonment.

Legal realism in some respect is superior to radical feminism. Here are some of the reasons
Unlike radical feminism, legal realism draws efficiency from hard-scientific facts. Indeed, it neither assumes nor prescribes political action. From the point of view of realists, political action without legal-scientific basis is not legitimate. The assumption of male supremacy in radical feminism is also problematic in the sense that it is not based on observable result of legal action

Radical feminism, while opposing socially accepted gender roles, is set to destroy the principle of gender equality by prescribing more power and position for women. In short, the legal basis of action is invalid or politically unsound as radical feminists do not believe in the efficacy of existing legal frameworks. Legal realism offers the best possible solution for this dilemma because it allows flexibility in the interpretation of existing laws

From (2) legal realism is indeed more flexible than radical feminism. Radical feminism often offers unrealistic and unclear solutions to existing problems. Legal realism can lead to acceptable legal decisions, if certain criteria are qualified and explained without bias

Consensus can be effectively reached under legal realism than in radical feminism. Note that the goals of radical feminism are almost uncompromising (creating two antagonistic camps)

And, legal realism, by its conservative nature, allows a cautious and methodological examination of facts relevant to certain legal dispute. This is almost impossible under radical feminism. Any issue which violates existing goals is deemed unacceptable and relegated to the position of undesirable.

In a sense, legal realism is inferior to radical feminism in three respects.

It does not recognize macro-realities  in this case, the reality that women are an oppressed group. Indeed, some of its critics argue that it is male-biased, that is, its focus cater only to the needs of males

Legal realism wholly lack initiative and swift political action. A legal dispute is often resolved by means of legal efficiency. As such, appendage issues are never tackled in their entirety. For example, realists argue that there is a clear line which separates who supra-related issues. The resolution of an issue can roughly lead to the resolution of another equally important issue

And, the realist view of politics is both cynical and conservative. It prevents political action from naturally occurring. It dreams and studies without the necessity for political action. Indeed, in the history of the West, it is often political action which institutionalizes social change.

Legal Realism vs. Utilitarianism
According to proponents of utilitarianism, it does not matter what kinds of acts individuals perform or what are the intentions considered so long as the effects of those actions are generally positive. The central tenet of utilitarianism can be summed up as follows pursue an action which will maximize individual or group happiness, taking into consideration the ratio between benefit and cost. An action which maximizes the good is a rational action. Individuals are encouraged to pursue such action. A strain of utilitarianism states that the greatest utility is that which benefits the greatest number of people with the least perceivable cost. Today, a significant number of laws are crafted based on this principle. Taxes, for example, are charged to individuals who derive most of the utility from state services. In some cases, tax exemption is imposed to encourage individuals to spend. In economics, this is called positive externality. The aim of these policies is to bring the highest utility for the greatest number of people.

Clearly, legal realism is superior to utilitarianism in several respects
Legal realism does not depend on the efficacy of number games. For example if a ruling results to the vindication of a criminal and such ruling is legally valid, then it cannot be theoretically overturned by the majority (this is of course hypothetical  in the real world, everything is possible)

Utility or happiness is not the sole criterion of legal sufficiency. As stated earlier, a legal dispute has psychological, sociological, and anthropological dimensions. In a sense, utilitarianism is essentially restrictive
The definition of utility varies from one setting to another. Indeed, groups define utility in an ambiguous manner

Under legal realism, the tenacity of a ruling depends on the perception of the receiving public. This is not the case with utilitarianism. It is often the immediate effect which shapes perception of acceptance
Utilitarianism is lacking in the sense that it fails to incorporate events which cannot be measured by acts of utility. This is not the case under legal realism. It is flexible enough to incorporate related causalities.

Legal realism is also inferior to utilitarianism in three respects 1) utilitarianism is a broad theory of social relations (unlike the former which is merely a specific legal view), 2) the latter demands political action while the former restrain, and 3) happiness or benefit is the major basis of legal ruling (which many realists fail to understand).

Legal Realism vs. Critical Legal Studies
Critical legal studies is a framework derived from the Frankfurt School. According to critical legal theorists, the law do not completely determine the outcome of legal disputes. To put it bluntly, the law often does not bind substantive rules to particular decisions in a case. Some theorists argue that the law itself is an instrument of the ruling or wealthy class.

The superiority of legal realism to critical legal studies is based on the following facts
One cannot really determine the actual intention of the lawgiver. If CLS is correct, then it can specifically show both the cause and outcome of a law. In legal realism, this is possible because multiple disciples are used in the study of legal predicaments

It is often difficult for CLS theorists to show that legal materials are inherently contradictory. In legal realism, such opinion is relegated to the position of indifference because the resolution of legal disputes depends on the legal framework itself

Legal realism takes into account equitable flexibility while CLS disregard the notion of a possible equity
The same case can be said for reliability. CLS theorists often argue that legal frameworks are not reliable in general. Now, how can a court of law resolve a case if its base of action is not even reliable
Other areas of jurisprudence (like international law) are partially ignored by CLS theorists. Realists incorporate this into their mainstream thinking.

Legal realism is also inferior to CLS in three respects 1) history shows that some societies crafted laws based on the interests of the ruling class (legal realism fails to take this into account), 2) the discourse of inequality is quite silent among realists, and 3) maintenance of social space is a topic ignored in legal realism (while magnified in CLS)

Conclusion
The prima facie difference between legal realism to contemporary legal perspectives is essentially based on focus and urgency. Clearly, in some aspects legal realism is superior to these theories while in some aspects inferior.