Seeing this reminded me that I have to finish these up too.
This game can be really annoying with the way it scores things, though. I feel like if you aren't following a pretty specific playstyle you can go fuck yourself. I get A+'s for every level where I do the same methodical "lure, punch, grab weapon, execute" process but when I feel like going the way more badass route of dodging gunfire and racking up a bunch of combos with a knife the game is like "Ehh".
Wearing Zack helps a lot. Just try a bunch and you can sweep entire floors in one or two combos.