I don't think RE6 had bad pacing because of the separate campaigns. I think it had bad pacing because... it just had bad pacing. It tries to keep the accelerator pinned for 20+ hours without ever trying to slow down or take a break, and it just gets exhausting after a while. I quite liked having multiple shorter campaigns with their own unique styles, areas and bosses, but unfortunately the game was just so bloated and messy the idea sank with it. I think a DMC5 with three separate, interlinking campaigns of roughly DMC1 length would be really cool.
I loved Yakuza 0, too, but keep in mind it's like 50 hours long so you have time to get back into the swing of things when you change characters (and Kiryu and Majima's playstyles aren't really all that different anyway). I don't think the same system of regularly swapping back and forth between Nero, Dante and V would work if you were chopping and changing every couple of missions in a game that'll probably be 15 hours long at most. And if you set it up so that, for example, you play the beginning as Nero, middle as V and end as Dante, I feel like that'd be even less satisfying because you wouldn't get to go through a full difficulty curve or story arc with any of them. DMC4 comes to a screeching halt and the difficulty curve more or less starts over in the middle of the game once you get control of Dante and have to learn how to play as him, and with V's playstyle sounding even more different than anything we've ever seen in DMC before you'd have two of those moments for DMC5 with a single campaign.
