Ardley took a chance on the 19-year-old Frenchman in January after he was released by Cardiff.
And Sainte-Luce put in a sparkling display on his full debut in Tuesday night's 3-1 win at Southend.
"Kevin Sainte-Luce started his first Football League game and we know what he is capable of with the things he can do on the ball, but he needs managing," said Ardley.
"He is still developing and he will have dips in form. But he is getting there fitness-wise and he can be a real handful for defenders."