Knives: Maybe some of the generic knives could be replaced, fine otherwise
a german officer's dagger would be great

Shovel: more power. A shovel was basically a wide knife blade on a long
handle. Plus it needs a satisfying "clunk"

Katana: 1 shot kill. I've taken Kendo one semester, and anyone trained with
a
Katana, as japanese officers undoubtably were, could certainly kill
or render a foe helpless with one blow, the targe areas are head,
throat, stomach/guts and arms.
Bayonets: i would really like to see these.
Feel free to add suggestions about melee combat!