Consider this:
The beginning of the game plays out the same but it's Credo who drops from the ceiling and shoots Sanctus. Tutorial fight plays out and Credo leaves after making cryptic remarks. As his subordinate, Nero is sent after him but discovers what the Order's been up to at Agnus' lab, heads back to HQ but Kyrie is captured, fights the revived Sanctus but gets captured as well, Credo comes in but is too late to save Nero. Then you play Dante's campaign but as Credo as he goes around destroying the Gates and retrieving Yamato from Agnus. He fights the Savior and delivers the Yamato to Nero who kills Sanctus and saves Kyrie etc etc. Bonus points if during Credo's campaign he reveals that he had met Nero's father, and that's why Nero should keep the Yamato, at the end Credo also reveals he's been in contact with a certain Devil Hunter who convinced him to rebel against Sanctus and will introduce Nero to him some day.
There, you can do the entirety of 4's plot without having Dante/Lady/Trish make a direct appearance. While Dante being in the game puts butts on seats, I still think it would have been better to have him sit out 4 and have Nero meet him proper in 5. Just my two cents.
The beginning of the game plays out the same but it's Credo who drops from the ceiling and shoots Sanctus. Tutorial fight plays out and Credo leaves after making cryptic remarks. As his subordinate, Nero is sent after him but discovers what the Order's been up to at Agnus' lab, heads back to HQ but Kyrie is captured, fights the revived Sanctus but gets captured as well, Credo comes in but is too late to save Nero. Then you play Dante's campaign but as Credo as he goes around destroying the Gates and retrieving Yamato from Agnus. He fights the Savior and delivers the Yamato to Nero who kills Sanctus and saves Kyrie etc etc. Bonus points if during Credo's campaign he reveals that he had met Nero's father, and that's why Nero should keep the Yamato, at the end Credo also reveals he's been in contact with a certain Devil Hunter who convinced him to rebel against Sanctus and will introduce Nero to him some day.
There, you can do the entirety of 4's plot without having Dante/Lady/Trish make a direct appearance. While Dante being in the game puts butts on seats, I still think it would have been better to have him sit out 4 and have Nero meet him proper in 5. Just my two cents.