Well Psycho Cut is a better choice than Psychic since Gallade has a high attack stat, but much lower special attack. For similar reasons you should probably replace Calm Mind and Miracle Leaf. Swords Dance would be a good replacement for Calm Mind isf you want a stat booster.
As for a good fighting move, you could always try Close Combat for it's high power, though it does lower both your defences by a stage afterwards. If you're not keen on that happening you can try Brick Break which is still reasonably powerful and gets rid of Light Screen or Reflect. You could of course opt for a slightly weaker attack, Drain Punch, which'll heal you for 25% of the damage it does. Since you're getting STAB bonus that might be handy.
For the last attack you could pick something that helps cover your team's weaknesses, like Rock Slide if you don't have anything in the way of Rock types, or try something which'll help Gallade like Thunder Wave.
Hope that helps.
