Most players will choose a Warrior Guild Cleric over a Light Weapon Warrior, at least with the narrow skill set you describe above. Other skill builds will alter the dynamic of that comparison.
In the early game, Agility Warriors using light weapons and a shield do well as every point of defense is notable. Duel and Flurry can make up a lot of ground, esp when paired with the stronger light weapons in the game.
But somewhere around the end-game, that advantage starts to slip away. Warriors have a better 2-H, and 1-H weapon selection; Infantry Training requires 1-H weapon, etc...
By way of further comment, you DO NOT NEED to use a light weapon with Flurry. An agility warrior wielding 1-H weapons, instead of light weapons, can get the jest of the build, without the limitation of the warrior's light weapon selection.
Lastly, why not have the warrior learn Massive Criticals and Precisions Strikes? There's not a guild lock issue at play, is there?