Nicolau, if Adam and Eve hadn't have sinned, would they need ruling over by God? Jehovah was their parent, not their eternal ruler.
What is the point of the 144,000 and who do they comprise? They are human corulers ruling over humanity. God is not ruling during the millennial reign, mankind is ruled by humans in heaven. Technically the 144k rule equally with Jesus, they are not subservient to him.
And there are references in Revelation to kings on earth, after the millennial reign.
Jehovah granted the Israelites request to have a human king, although he warned it would bring trouble (because they were appointing a human dictator). God recognised the Israelites right to self-rule, as imperfect as the arrangement was.
What normal father does not naturally want and lovingly nurture his children to become mature, independent, self sufficient, morally responsible persons? It's an intractable contradiction for JWs to claim God is there father and that they are his children but that they are forever incapable of independent self rule.