You give a good example: which policies towards the market create more wealth (on average, various things being equal) is a matter of fact. But I think this sort of non-arbitrary approach to thinking has much wider applicability, and indeed that all interesting subjects can be approached in a careful, meaningful way not based on personal taste.
Which policies are ethical, with "ethics" rightly construed, is also a matter of fact. Morality is about how to live, and it's not a religious concept. The notion that morality is (and must be) religious is unfortunately a bad, religious idea, that (oddly) most atheists still believe.
Just to get started, we can consider which lifestyles do and do not accomplish their own internal goals. Lifestyles that do not are bad ways to live -- they are "immoral". We don't have to use moral terminology; that isn't important. But whatever you call it, there are objective facts about how we should or shouldn't live.
And there's better than that. You can take a very wide variety of goals, and examine how to achieve them. And you can find common points -- certain ways of life are good for achieving many goals, while others are not. These common points, which make people powerful and able to accomplish things in general, are an important, useful, and objective find the field of morality.