I want to hear about the consequences for individual preferences of alternative policies. Who gets effected by the policy. Furthermore, you need to say why this difference makes a difference. Yes, doctors tend to wear white coats, so they are different in that way, but to use this difference you'd have to say why white coats matter for the case at hand. Keep in mind these standard economic rationales for intervention.
Air pollution is an example.
Problems can happen when things some people do effect other people, and those first people do not take that effect into account. Problems can happen when some people know things that others do not, and attempts to reveal or hide that information induce some important inefficiency or waste. An example would be a small country tempted to nationalize the phone industry after foreign investors build a phone network. Be clear about whether you are assuming people are rational, as in the usual economic models, or whether you are assuming they are irrational in some particular way. Cite your sources.