Is the Commander a sympathetic character, a monster, or both?

The commander sounded more like a naive needy boy rather than an all-powerful chief. He seems to have the need for both a mother-figure, a friend, and a sexual partner in Offred. I don't think he is a monster. His powerful job bellies the fact that he is very much the typical cheating male who uses infidelity as a cliché: he claims that his wife simply doesn't "understand" him.