Steven Novella, whose Skeptics’ Guide to the Universe podcast is one I never miss (also check the brief companion 5×5 podcast), is trying out a new definition for a perfectly good word that others (for some reason) don’t seem too keen on, namely “skeptic”:

A skeptic is one who prefers beliefs and conclusions that are reliable and valid to ones that are comforting or convenient, and therefore rigorously and openly applies the methods of science and reason to all empirical claims, especially their own. A skeptic provisionally proportions acceptance of any claim to valid logic and a fair and thorough assessment of available evidence, and studies the pitfalls of human reason and the mechanisms of deception so as to avoid being deceived by others or themselves. Skepticism values method over any particular conclusion.

I jotted some notes that I reckoned others might find interesting or informative and thought it best to reprint my comment here:
As a classicist I can tell you that the original meaning (Gk. skeptikos) was simply ‘thoughtful, reflective.’ It comes from a verb that describes a careful kind of looking. The idea of doubt came from a term also used to describe a certain kind of thinker: aporetikos. It isn’t difficult to see how giving careful attention to philosophical questions (which in the ancient world also meant scientific questions) would lead one to be a doubter, in the same way that careful (i.e., critical) thought among modern skeptics leads us to doubt traditional explanations.
This same type of thinker could also be called ephektikos, which is something like the modern coinage agnostic. This referred to someone as suspending judgment. What it really means is that you hold yourself back and look at things impartially. This is something else that we do, and it allows us to criticize the emotional responses of others.
The three terms are closely associated, but one gave its name to a school. And as with many schools of thought through the ages, its opponents (like modern theists in the face of a resurgent atheism) took great pains to tar its practitioners.
Far from being sub-optimal, I think skeptic is about as good a word as we’re likely to find, and together with its companion adjectives (which have colored its reception) covers just about everything in your definition.