The discussion about the relative values of a "Jack" merc vs. a "Max" merc didn't mention HTH but it still would apply. A merc maxed for HTH would be considered a "specialist". As such you wouldn't want to create a squad of all HTH mercs any more than a squad of all Engineers. Not in a game where firearm combat is the norm. Think square peg/round hole. It might fit but it won't be a perfect fit and might need a BFH to fit at all. Might be fun to try it once but I don't see it working for an entire game. But like the other specialists, used properly in the right situation, round peg/round hole.
Building a "Max" HTH merc. Give him the AGGRESSIVE character for "slightly bigger damage in close combat". After selecting MARTIAL ARTS you can select only one minor trait. This is where it's decision time, HTH weapons or bare hands. HTH weapons would choose MELEE with a background of HITMAN. Bare hands gains little benefit from MELEE so either STEALTHY or ATHLETICS. Neither directly affects HTH combat but both have advanantges that make it easier to get there. Backgrounds of BOUNCER, HITMAN or WRESTLER all have pluses but also minuses, none are a perfect fit. Pick your poison.
Another possibility is SPY instead of MARTIAL ARTS. Even when not disguised there are significant advantages to HTH. When disguised, walk right up to him. Sometimes you can even pull off a kill without losing the disguise.
One HTH weapon often overlooked is the Stun Gun. A hit is an instant KO followed by an auto kill or a prisoner.