I think you nailed it on the head. The Prime Mover argument (and just about every god argument I’ve ever come across) is just personal bias parading as logic. That’s not to say Aquinas was trying to be deceitful and certainly not that he was dumb. Far from it. I think it was more that he was trapped so to speak in an intellectual box that wouldn’t allow him to think that effects may be uncaused or that it’s possible that our puny little minds might not be capable of even conceiving of the logic (or lack of logic) behind the universe.
And that’s the problem with any kind of god talk or talk of ultimate things…we just don’t know what we’re talking about. Sure the sentences may make sense, but anything else is pure guess work. A good example is this prime mover argument. Maybe the prime mover is the devil. Maybe the prime mover created the universe with parts that don’t follow any logic at all, and she did it on purpose! I mean come on, she allowed nuts like Pat Robertson to be born, she has to have a sense of humor. It’s all just stories we make up, and the smarter of us makes up stories that SEEM believeable.