I think the best thing DMC5 could do story wise is to move forward and not dwell on the past. The franchise needs to get past circle jerking about Sparda and establish that Dante (and Vergil) have both surpassed him at this point. Open the game up with a set of new villains showing up, perhaps some kind of primeval demons that neither Mundus or Sparda knew about, have them scoff at the legend of Sparda and be all like "that guy wasn't even shit" and have them try to take over Earth. Dante needs to find Vergil in order for CUHRAZY JACKPOT TIME, the story is about Dante and Vergil truly surpassing their father and setting up their own legacies instead of cleaning up their dad's messes.
Alternatively, take a page out of Bayonetta's playbook and instead of having demons as the villains perhaps make this game Dante vs Heaven. Just say that God and company think Dante's too powerful of an out-of-their-control force. Seeing Dante trying to throw shade at God would be pretty crazy.
Alternatively, take a page out of Bayonetta's playbook and instead of having demons as the villains perhaps make this game Dante vs Heaven. Just say that God and company think Dante's too powerful of an out-of-their-control force. Seeing Dante trying to throw shade at God would be pretty crazy.