Answer

As for Maimonides, I don’t know. It also depends on where he writes each thing, since each of his works is directed to a different audience and says somewhat different things. The explanations for the commandments in the Guide for the Perplexed are really not convincing, but they were probably intended for the perplexed. And as is well known, there are contradictions between the Guide and the Mishneh Torah. But I haven’t examined Maimonides’ approach on this issue, so I can’t say anything definite.
I do accept the division. Who doesn’t accept it? It’s a fact that there are commandments that accord with reason and others that do not (in the Laws of Kings Maimonides describes the seven Noahide commandments as things toward which reason inclines). The only question worth discussing is whether this division has any halakhic or other practical implication. I don’t know of any such implication. There is Maimonides’ discussion in chapter 6 of the Eight Chapters about the superiority of the person who rules over his inclinations with regard to revelational commandments, and the superiority of the intellectually virtuous person with regard to rational ones. But even here this is not really an implication of that division, because the identification of the virtuous person is not necessarily with the commandment itself, but rather with the moral principle that parallels it. So, for example, it may be that someone who identifies with giving charity is preferable to someone who gives as if compelled by a demon (that is, one who suppresses his inclination). But the identification is not with the commandment itself—for this is a commandment like any other revelational commandment—but with the moral principle of giving charity.