For me it would be simple, mix DMC with Dark Souls 1 Atmosphere.
Have Dantes shop as a hub from where you start main missions, those missions would graually unlock parts of the world. And let us explore that world outside of missions to unlock blue orbs and stuff. Also make it so that there are secrets specific to other playable characters (if there are any).
If we got the classic weapons back (Sword, Gauntlets), then give me the ability to change their skin to different other weapons we already had in the series (like in DmC with the weapon skins). That way we could customize the look of Dante a bit better.
Have Dantes shop as a hub from where you start main missions, those missions would graually unlock parts of the world. And let us explore that world outside of missions to unlock blue orbs and stuff. Also make it so that there are secrets specific to other playable characters (if there are any).
If we got the classic weapons back (Sword, Gauntlets), then give me the ability to change their skin to different other weapons we already had in the series (like in DmC with the weapon skins). That way we could customize the look of Dante a bit better.