I don't follow your economic and ontological line, I would have problems if I did, as you have now, but are unable to admit.
You like to try and reason everything out to fit your preconceived ideas. I simplyt accept the plain statements as written. I know man in his wisdom is quite prepared to contradict the plainest of statements in the Bible. But mans own natural wisdom is his downfall with God.
The concepts are valid concepts, whether you want to recognize them or not. For example, I am a human that's who I am, it's part of my essence and my being. Do you think that is a valid category?
If humanity (or humanness) is a valid category, then what are you objecting to? Do you simply dislike the term "ontology"? I'd be happy to use different terms if that's the case.
I also have a job. That's what I do. It's how I function. I have a boss. He is my superior. He isn't my superior in that his essence or his nature is superior to mine. He is superior to me only in that he has authority over what I do, how I function.
Is functioning a valid category? Is it possible to have the category of ruler and/or servant? If those are valid categories, then what are you objecting to? Do you simply dislike the term "economy"? If so, we can use a different term here too.
Now, 1 Corinthians speaks of Jesus being ruler. That's a function. Do you agree?