As it stands, there's no way to tell. All three of them have improved since Soul Society (Byakuya trounced the Espada with the fastest Sonido easily and used a new move with his Ban Kai, Kenpachi is self-explanatory as well as Ichigo).
Once we see Byakuya and Kenpachi go all-out once again, we can make a more accurate judgment.
As for the whole Byakuya vs. Ban Kai Ichigo thing...none of what you said really means a thing. Byakuya's arrogance is what created those openings. Just because Ichigo took advantage of that twice doesn't make him the stronger fighter. Before any of that, Byakuya could have easily finished off Ichigo when he took on Byakuya's Ban Kai without using his own, but Byakuya's curiosity and pride got the best of him.
And Ichigo's "worn bones" don't come into play when Hollow Ichigo takes over, since he pushed Ichigo's Ban Kai and reiatsu to the limit but could also force Ichigo's body to handle the stress. Let it be known, that when Ichigo's Vizard abilities are being controlled by his Hollow, his reiatsu skyrockets, even surpassing Ulqiorra's apparently.
Well that's all I say on that matter. Going back to the main topic, it's a game of wait and see. Byakuya made an absolute joke out of Zomari, and it would've ended even faster were Rukia not there.