So the fact that someone is religious --in the sense that the religious world takes it to mean--has nothing to do with the question if they are a decent human being-.

Morality and one's belief system are two separate areas of value. Even if they are related they are still dealing with different subject matter.  So the fact that someone is religious --in the sense that the religious world takes it to mean--has nothing to do with the question if they are a decent human being-. In fact it was this revelation that caused me to be less enchanted with the religious world.

Furthermore it seems to me that the amount of mental energy that people put into religious observance seems to take away how much energy they can put into being decent people.

You can see in the writings of Rav Israel Salanter and also the events of his life that he wanted to solve this problem. It could be that he had succeeded to some degree in the Litvak yeshiva world--where his teachings were more or less accepted.