I'll say it again, I love Kenny dearly, but he is not the MC, nor can he stand alone against the enemy. Haven't you understood why Byakuya and Kenpachi are shown as 'frenemies?' Kubo is pointing out how friends and even friendly rivals all need each other to succeed. It's a group effort.
You are still trying to undermine that Kenpachi killed the strongest Sternritter and destroyed a meteorite 150-250KM in size. It's not like he fainted and dropped in the ditch, he tanked multiple nuclear explosions generated from Gremmy at point blank range and was still able to finish the fight standing all that while STILL using his eyepatch.
Kenpachi : 4
Byakuya : 0
Kenpachi : 3
Byakuya : 0
Best power feats :
Kenpachi : Destroying an insanely large meteorite in a single swing. Defeating the most senior captain that claimed to be the strongest. Killed the most powerful Sternritter. Used to be stronger than Unohana an exceptionally powerful captain as a child.
Byakuya : Large building destruction feats in bankai, capable of using 80s kiddo without incantation, fast shunpo. Versatile combat. Best tanking feat was that he barely survived the damage of his own bankai.
There is simply no comparison between the two. Kenpachi is miles ahead of Byakuya.
You are still comparing recent Kenpachi to a Byakuya from whatever time ago, so, it's not like we are going anywhere with this debate. I don't really want to go in circles anymore, but to restate in short, the power curve is largely dependent on the measurability of the abilities, with more vaguely perceived powers taking up higher ranks. The more vague an ability is, the more capable the fighter becomes, as a generalization in a simple way.
Regardless, this is a debate about Byakuya and Kenpachi representing polar opposite sides, thus, having a rivalry of sorts within the story. Too much power level talk interfering. I feel like we are discussing the same stuff in two separate threads at the moment, so, yeah.
As far as ideals go, I don't think that Zaraki and Byakuya have similar roles in the story whatsoever.
Byakuya is a samurai by every way you look at it. He is a personal that strives for perfection at everything he does, respects the customs and upholds the law and traditions. He is a very honorable fighter and somewhat cruel. Although this changed later in the story where he became more empathetic towards his followers and people that are close to him. His character development could be summarized like this "He became softer and less robot-like". That's the main point about Byakuya. He was a person that felt that he had "too much" to prove. He felt the weight of being a noble and a prodigy as something he had to endure no matter the cost . Even if that meant scarring him. After his fated battle with Ichigo he understood that he couldn't be a role model for anyone if he couldn't be good with himself, and that sometimes traditions and customs are less important that protecting the thing that is truly important to you personally.
His Shikai/Bankai shows exactly that as it's "form" is a samurai in full armor and the actual appearance looks like a sakura something that is very "traditional" and elegant".
Byakuya is the Samurai that learned the value of also respecting and caring about the people close to him. He became more human.
Zaraki is a free person but still respects the obligations he has to follow assuming it helps him accomplish his goal, a goal which is to fight powerful warriors. At first glance he doesn't seem that he shares an alliegance with anyone. He is a person that lives for battle, every single action he takes is to ensure he can keep fighting. He doesn't care about winning/losing so much, but rather prefers to have a truly intriguing battle to the death. He is someone that never fought people equal to him and that caused some severe mental issues which resulted in him putting mental barriers to supress his power. Later in the story he slowly started showing some form of discipline and empathy towards his subordinates and also started making friendships, something which is very strange to a mindless killing machine as Zaraki. Currently he stopped fooling around and truly embraced the title "Kenpachi" accepting his place and destiny within Seiretei as the "Monster" of Gotei 13. Zaraki used to be all about fighting and killing and now is starting to become a complete person that cares about the people around him, even his own zampaktoo.
His Shikai/Sword also shows exactly that by having no name for the most of the story and when it finally found it's name unleashed it's true form. Similar to Kenpachi, he had no name and no purpose and was "weak" and now that he has a name and a purpose he is unleashed.
Zaraki is the lost soul that seems to finally learned his way. A person that had no name and no identity but only raw power, finally found a name and a purpose to use this power.
Byakuya had too much burdening him and found a way to balance things out.
Zaraki was a soul soul which found his purpose.
A couple of nice points in defining both, though I still somewhat see a vague connection between their paths.
Byakuya was a man who got lost while upholding the code of honor left behind by his family, getting stuck in the past, losing sight of what was really important to him. Kenpachi lost his identity along the way of his slaughtering of people. He did not get stuck in the past, but rather, in the present, because that is what happens when you no longer have sight of yourself.
One relied on morals, the other relied on fights to keep their sanity, or in Kenpachi's case, half-insanity. In better words, they kept track of the traces that defined them as beings. That's the similarity, I'd argue.