What an awesome giveaway, thanks for the opportunity!
I like the lines of the pocket kwaiken the most out of those four and think it would look absolutely fabulous with some darker colored wooden scales (ziricote, ebony or perhaps grenadill ) and titanium bolsters if that's an option.
I assume that titanium isn't an option though, since it's so hard to work with, so I'm going for bocoto scales with black micarta bolsters and a thin black liner.