Yakuza: Kiwami is Kazuma Kiryu's first outing, but it's been remade to look even nicer and play even better. And by this, I mean that self-proclaimed "Mad Dog" Goro Majima will pop out of bins and manhole covers to fight you with even more gusto.
I played Kiwami soon after I finished Yakuza: 0 (as is the right and proper way), and it felt like a step backwards. This isn't to say that it isn't good - far from it. Just don't expect it to match the prequel's impeccable, well, everything.
Instead, I'd treat Yakuza: Kiwami like the important piece of video game history it is. This is where Yakuza started after all, and from here on out, you get to see how Kiryu and the gang evolve as you go from one, to two, and so on.
Largely this process involves getting tanked by Majima at every corner turn, and bellowing "bakai mitai" at the karaoke parlour until your lungs burst.