I'm not visiting during the opening month... But if I were I'd keep in mind that opening day is just a day, but this park is intended to be here for 50+ years. A lot is going to change. A lot is going to be improved rather quickly. Some things may take a couple years to iron out.
USF didn't have any background music when it first opened, because it was attempting to resemble a real-life working movie studio and backlot... And for that you need there to be "quiet on the set!" It felt weirdly calm in the park. Like a Twilight Zone episode. They fixed that mistake real fast... (Although the music in San Fransisco needs to be updated like 15 years ago. Smooth by Rob Thomas, still? Barenaked Ladies? Doesn't really scream San Francisco to me.)
I'm super excited Universal built their own water park. And the rides look amazing. But I expect it to not feel like the tropical getaway they're going for for another year or two. After the smell of fresh paint wears off. And the foliage fills out. Until then, it's going to have that new theme park smell, and probably even some ill-advised choices that will quickly be remedied after the sound of 10,000 bloggers fills the Twittersphere.
It's not day one I am concerned about. More like day 500 or so. That's when it should be coming into its own and be a more complete feeling park.