If I can recall TC GameCube graphics were the strongest of its era.
No, actually the X-Box was the strongest of the era, graphically, but the difference between the three was generally so close as to be negligible anyway except in very rare cases.
And actually I thought the game looked absolutely fantactic and... honestly I'm not sure if the characters were rendered in 3D or not. I think only some of the elements and backgrounds are 3D while the characters are still 2D. Either way I thought it looked absolutely fantastic.