Chucky's eyes were inconsistent.
Just rewatched the trilogy.
One thing that kept bugging me about this movie was Chucky's eyes.
In 1 + 3 his eyes always look like a Good Guy Doll. He often furrows his brows in rage, but his actual eyes look like the doll's eyes. It is one of things (especially in the first one) that makes him so creepy. During the shots where he's just an inanimate doll, you know that he's just waiting there keeping perfectly still and there's a lot going on behind the eyes.
Now in this movie his eyes change a lot. When he is in inanimate doll mode, his eyes look like the lifeless pale blue eyes of a Good Guy doll as they should. However, whenever he is exposing his true nature and being murderous Chucky, his eyes look COMPLETELY different. His irises become bigger and a darker shade of blue, as if he somehow has the ability to morph his eye appearance at will. It's not a huge deal, but I found it somewhat distracting especially since there's no real good reason for it to happen.