I'm going for fastest possible completion time. This game has a somewhat frustrating menu system for item control which makes for a difficult time attack, though it's possible I could do this better, but I doubt it would reduce the time that much.
Nightshade has several objectives, including collecting items and completing (side-quests?) to gain popularity, none of which seem to be necessary to complete the game.
I pretty much just bee-lined for the bosses and killed them. This was/is a pretty fun game; I hope it makes for a somewhat entertaining movie as well.
The initial goal was for fastest time/no damage, but in the sewers, that would involve some waiting around; i don't think luck manipulation works on the bats, they seem to follow a set course.