Here's a recipe for an absolutely insane physical unit:
Take a Monk, and raise their Bravery and Strength scores, so that their single hits deal obscene damage.
Give them the Ninja's Dual Wield support ability, that lets them attack twice (or, alternatively, apply the Monk's Brawler to a Ninja). Obscene damage x2.
Now give the Monk/Ninja the Archer's Aim action ability, and use the CT counter figure out the highest Aim attack you can use on the opponent in front of you before their own turn goes off. The charge attack will not only ramp that already obscene damage, but it will apply to both punches. Your unit can now take out anything in a random encounter in a single action, and shut down most bosses in a matter of rounds.
Finally, give the Monk/Ninja the Samurai's Shirahadori reaction ability. The previously-raised Bravery score will be directly converted into an avoidance percentage for any physical attack, which maxes out at ninety-seven percent in order to prevent the enemy from just not trying.
For added defensiveness, drop their Faith scores as low as you have the patience for, thus reducing the damage that magic can do to them; the minimum Faith score is three, which will cause magic to have an absolutely piteous effect (or, alternatively, have a Mystic in your team to apply Atheist, which gives them an effective score of zero and lets them No-Sell it).