"Kristin Chenoweth doesn't STOP being cute". Well, that's silly! Of course she does! Because you need those dramatic moments (mostly in Act II) so you can have something to compare her cutness and sillyness to. You can't have comedy without the drama.
Second.
Saying that J-La can't reach those higher "optional" notes is scary and that is what made the show/role "amazing" is quite silly as well. Would it really knock down the show from "amazing" to "pretty good" if one of many characters takes a note down about 3 or 4 steps for probably a mere 6 seconds of total time?
I'm sure the whole rating of a show would not degrade because of optional notes taken. If that's the case---you are looking too finely into what makes a show "great". I.E. 2 notes throughout the entire show.