I think that, if it is at all possible, the attack roll should affect the animation- a fighter who rolls 16 and hits shouldn't have the same animation as a the same fighter rolling 8 and still hitting. it could even be used to reflect the prowess of the attacker- a combined modifier and roll of 29 should have an animation far cooler than that of a combined 16 even if they both hit, it simply reflects the fact that the first is a far more skillfully made hit, and is also a good way to make the player feel his charecter is getting better as it levels, not to mention being outright awsome.
P.S.: the Illithid model is a true masterpiece of 3D art, and who ever made it should get a medal.
