Sorry man, but your post doesn't make that much sense.
Nakaba introduced the sins one after another and began powering them up one by one in a different pattern.
Meliodas received PU COUNTLESS times, King, Gowther, and Diane two times each, Ban and Escanor had one, and Merlin got none.
It was Nakaba's plan from the start to make them more powerful, so in the process, there were moments in which a sin surpassed one or several of their stronger allies temporarily.
Comparing full grown King with Merlin or Escanor who had never been the focus of the story until recently was heavily flawed. How can we compare someone who's plot is nearly completed (King, Ban) with someone whose plot isn't actually started (Escanor, Merlin)?
It's not Nakaba's change of plan when he had always intended to introduce Escanor as the strongest. It was the fandom who doubted the very words of the author himself in favor of their headcanons.