First off, I'm just gonna assume everyones already seen Bleach so I'm not bothering with the whole spoiler alert, cuz if you haven't well yeah.... I just feel that this part of the arc is so underrated. I honestly feel that even though there was no epic fight to finish the Aizen arc, this was an ending fitting of Kurosaki Ichigo. Ichigo always seemed scared to use his inner hollow powers, especially after he died and his hollow took over.
Gotta admit though, I liked the no bs killer hollowfied him better. Even if he almost broke Hell. But that's another story. His inner hollow did warn him, if he ever let up, he would take his "king" position. It's only his pure strength of will that has gotten Ichigo anywhere. But that's where it gets better.
Ichigo was meant to get stronger, a lot f'n stronger. When he went to train in the time loophole thing (I haven't kept up with Bleach terminology lmao) it kinda revealed that his power was meant to fuse. Both banka and his vizard mask was what I assume (or actually hoped) would have been like an espada but higher up with shinigami power. As in, shikai, bankai, mask fragment to full mask, then full hollow form but under control. Tbh I thought that was why they gave Ulquirria two forms. To show the possibility of Ichigo fully unifying with his hollow. . . kinda like how Naruto and old nine tails had full trust in each other. . . . which is probably why they didn't do it. . . huh. . . writers are whack. Either way. Ichigo couldn't bring himself to ever trust his inner hollow. Which is why he learned the final getsuga tenshou attack. Even after he had gained all that spiritual power, fought with Aizen, was obviously stronger, he still gave it all up. He knew the sokyouku (sorry I didn't spell it right, wish I could go full otaku) was only going to keep on feeding Aizen power, and a drawn out fight would have destroyed soul society. So instead, he spikes his power to the max, and let's out a concentrated black lunar fang attack. He gave up his whole shinigami life and future, to make sure Aizen was defeated. I don't know that's just my point of view. Still don't like where the story went after that. It's cool they wanted to explain the whole story, but I kinda like to think that the Aizen arc is where Bleach truly ended.