I read philosophy and political philosophy for at least an hour a day. I'm not kidding. In addition to books and the invaluable Stanford Encyclopedia of Philosophy, I often run Google searches for terms or people of interest with "filetype:pdf" so I can read all of the papers, articles, and dissertations available online. One day it'll be "responsibility-catering prioritarianism." The next it'll be "Philippa Foot." I read a lot.
The biggest lesson I've learned is that most ethical models make a lot of sense, while simultaneously being subject to compromising flaws. Utilitarianism and other forms of consequentialism capture something that almost everyone intuitively agrees with: you should do what's best. Kant and other deontological theorists capture another something almost everyone agrees with: we have duties to one another beyond the "greatest good." Contractualism, be it Rawlsian or Scanlonian, is built on the insight that we are social beings and must justify our actions to one another. The various species of virtue ethics confront the question that we've all asked ourselves: how do I be a good person? Even so-called "ethical" egoism arises from an innocuous premise that we seek our own well-being.
But none of these theories is compatible with each other absent tremendous mental acrobatics. For that matter, various varieties within each theory aren't compatible with each other. Peter Singer and Brad Hooker are both consequentialists, but their accounts of what we ought to do are incredibly different.
On top of all that, biologists and psychologists are uncovering the evolutionary history of morality. There really seems to be a moral instinct, derived from the psychological needs of social great apes such as humans. We have instinctive urges to, say, not harm each other under normal circumstances, to reciprocate when someone helps us, to help others, and so on.
It seems to me that the major moral theories are constructed by instinctively feeling one of these urges and running with it to the exclusion of all the others. Utilitarians feel the instinct to promote the general welfare and declare the general welfare is the supreme good — all the other instincts either service this good or are mistaken. Contractualists feel the instinct to reciprocate and declare mutual agreement the basis for morality — the general welfare is merely a side effect.
The reason most people don't give philosophy much thought is precisely because most people just go with their gut. We all have a commonsense morality already, and while it can be led astray by experience and culture (see also: the evil of religion), it's good enough most of the time without resorting the lexical rules and utilitarian calculus and so on. Obviously, I wouldn't spend so much of my free time reading about this stuff if I didn't find it both interesting and important, but it must be put into perspective.
As it turns out, there is already a moral theory that does a fairly credible job of capturing all of our instincts and even our decision-making process. Unfortunately, it is general enough that, while influential, it is largely rejected by professionals in ethics. This is the pluralistic intuitionism of WD Ross.
Ross holds that there are prima facie duties that we have towards others. If there is only one duty in a situation, it is our duty proper and we ought to do it. If there are more than one duty in a situation, the more stringent becomes our duty proper that we ought to do. What makes Ross's duties different from, say, Kantian duties, is that Ross makes no claim to an overarching principle from which duties can be derived and identified. Ross says that prima facie duties are just self-evident, and deciding between them is done simply through the application of moral judgment. Duties are reasons that inform our actions; they are the justifications we might use to explain why we think what we did was right. To Ross, a moral theory should fit the facts as they are, even if it isn't a tidy little package. He compares ignoring our (fully-considered, reflective) intuitions because they conflict with a specific moral theory to refusing to enjoy something beautiful because it conflicts with some theory of aesthetics.
You can see why philosophers aren't happy to embrace this idea.
But one has to see the parallel between prima facie duties and moral instincts. Ross's canonical list of duties (he says there may be more) includes: fidelity, reparation, gratitude, non-maleficence, justice, beneficence, and self-improvement. These are, remarkably, pretty much the sorts of things one would expect to evolve as aids to group cohesion among a young species of big-headed apes.
I think that Ross, ultimately, is right. I disagree with him that morality is part of the "fundamental nature of the universe" in the way that geometry is, but in terms of what morality is on the ground, I think that the idea of potentially conflicting prima facie duties that are resolved by making a judgment call is correct.
That doesn't mean I think utilitarians and deontologists and the rest are wasting their time. To the contrary! I think what they do is crucial in unpacking our moral judgments, and I think studying them is part of the duty to self-improvement — the instinct the virtue ethicists latched onto and ran with. It is only by understanding how and why we make choices that we can make them well.