Here are a couple of things from my perspective:
1. Aiki is not morality. I think equating aiki with a [good] morality leads us to make erroneous judgements about what is and is not aikido. Saying something like "uke is not doing aikido because he was to cut off nage's head" presumes that the person cutting is bad. This presumption may be wrong.
2. Harmony is subjective. We use word like harmony in aikido with the presumption that harmony as we view it is the absolute harmony. This presumption may be wrong.
Both excellent points.
There's an old saying: you can safely conclude that you've created God in your own image when it turns out that God hates all the same people you do. If you think all of your actions are necessarily "good" because you are using aiki, you probably don't understand aiki very well.
(A point that becomes obvious when applied to other people...)
Morality is morality. Aikido is aikido.