The Kick Attack maneuver in Arsenal p160 reads:
A staple of many martial arts, kicking has a greater range and power than punching. The attacker receives +1 Reach on Unarmed Combat Tests when using a Kick Attack.
No requirement, straight bonus, no malus.
From a mechanics point of view, is there any reason not to use a Kick Attack maneuver on all Unarmed Combat attacks?