The moves could be split into these groups: hand attacks, hand combos, foot attacks, foot combos and hand-foot combos. For example, the character could have Jab, Cross, Uppercut, Elbow Smash, Backhand, Sucker Punch, Spearhand, and Ridgehand as standard hand attacks, each with their own AP cost, bonus or penalty to hit, DT modifier, and damage. However, the character could also gain "two-in-one" combos.
For instance, Jab-Elbow. The combo would do both moves, each at a different hex. The Jab would go into the targeted hex, and the Elbow Smash would go into the hex back and to the right. The combo would cost less AP than both moves individually, but it would be at a lower chance to hit with each attack, and would incur a fatigue cost. Another combo might be Cross-Backhand-Ridgehand, hitting the first hex targeted, the hex to the right, and the hex two more to the right.
Kicks could have the same general layout (with different moves, of course). The kicks don't even have to be crazy wire-fu'ed out. They can just be regular ol' kicks. Snap Kick, Axe Kick, Roundhouse, Back Kick, Side Kick, Hook Kick, etc. You could have the same sorts of combos. Roundhouse-Hook, Side-Back, Snap-Side-Axe.
The most complex combos would only be available when the character was fighting with no equipment in either hand, allowing hand-foot combos that could hit four, five, or even six hexes.