Should we allow normative questions on the site or will they be too prone to political debate?
Well questions of normative economics are often of most interest to visitors; but it's a matter of quality and context: Does the question demand a desired answer? Do the answers reply without using recursive normative statements of their own? Do the value judgements backslide into politics or philosophy?
If we do allow and enforce them, we have to allow and enforce them equally across all ideological biases - otherwise some members will get driven out by others and at the end of private beta you end up with moderators of an inherent ideological bias that cripple the public beta.
The key concept in my mind for a good normative question is respect.
Does the question respect the audience? Respect posting etiquette? Respect ideological diversity? Respect the scientific method? Does it avoid talking about politics and religion at the dinner table?
Bad normative questions ooze disrespect and don't improve with prompting from other people.
The science takes no stand on this, so I would tend to disallow them. This is not philosophy.
Referring to the comment regarding Gini
Economics as a science takes normative values as given. For example, papers in optimal taxation need some kind of normative standpoint. They will typically take Utilitarian-welfare measures with Pareto-weights just for the sake of the argument. These are assumed as given, you will not see a discussion about the optimal welfare weight.
The reason is not that Economists are all utilitarians, it is mainly that this is an accepted stand to take (we need to take some stand, so just care about everyone according to some weight). You will typically not see discussions about different welfare measures, unless it is some kind of a robustness check of the original results.
Gini is used as one measure of inequality. That being sad, scientific papers do not take a stand on whether inequality is good or bad. They may, however, infer whether it is good for growth (there is a huge strand of theoretical and empirical papers that tries to infer about this relationship) or similar measures.
Piketty has restarted the old debate about Inequality. But even he with his French background did not dispute whether inequality is good or bad per se. Instead, he argued that extreme values of inequality will lead to social unrest and turmoils and hence paths that will lead to such extreme inequality being suboptimal.