My list in addition to dwarfkicker's:
- Rework the voice acting in addition. Drew Coombs for Dante, competent voice actors for Lucia and Arius.
- Tie DMC1 and 2 together in terms of story.
- Rework/completely replace the levels. Would likely completely redo the blue orb things that had to be wailed on to unlock things.
- Likely give the boss' the gift of speech and a story connection rather than them appearing from nowhere and attacking.
- Would rework all the bosses as well as omit/replace some.
-Replace the sounds completely. E&I should sound like E&I and Dante shouldn't sound like he is wearing women's heels.
-Redo the music, a mix of classical and contemporary in line with DMC1 maybe a DMC3 style vocal track or two but just for the credits or something.
-Omit the sub machine guns, fairly worthless weapons and not stylish enough.
-Clearly defined and useful moves. Maybe a style system or at least a move set assigned to the weapons.
-Omit the amulet/heart system.
-Redo the devil trigger system more inline with 1 and 3. Omit the desperation mode.