yeah i see this opinion often and some of you dont pay enough attention to the manga. the whole point of this final arc is that the reason for every corruption and the reason Takemichi had a hard time for so long was because Mikey kept getting corrupted and was easily able to stray from his path. Do you understand how unfulfilling an ending is when a character doesn't even get the development they deserve and it leaves a huge amount of plot armor? The author is doing something amazing to wrap up the work effectively and make all the character endings make sense. Just cause you can't notice such obvious character details, doesn't mean that nobody else noticed them.
While I respect your opinion because i used to think that, this is the last arc that everything is finally going to be explained. The last arc ending was heavy but pretty needed imo. [after this there are spoilers] every single ending, besides hina dying, mikey has either been missing or with another gang doing dangerous shit. After the hina situation was fixed( kisaki dead), the missing piece is still mikey. While it seems like its getting dragged out, every arc and there futures contribute to one another. It also shows how while hina was the main focus, as he got closer to the manji gang, he realized how everyone else needed saving from a horrible fate.. especially mikey. Honestly i love it so much I don’t want it to end so i have no problem but yea.
Okay so this is too much for me.. I think is should've ended with a happy wedding (ofc happy end for Mikey too). It keeps dragging on forever.. I think the last time trave is just way too much and useless