Also want to add my thanks to Soniam for this thread. Without all the information that I gathered in this thread, I would have come into the park unprepared and not had the great experience that we were able to have.
Visited on Tuesday, August 29th. Arrived at 7:40am for Early Hours for Universal Hotel guest and the line was already about 20 deep at the turnstiles. Around 7:50am, they started letting people in.
Between 8:00am - 10:00am, we rode every slide in the park except for Ko'okiri (the body plunge from the front of the Volcano). I followed the order that was suggested a few pages back. Crowd seemed to be pretty low and everything stayed Ride Now for the 1st hour. But Oh'No and Oh'Yah around 9am, changed to 20 - 30 minute waits. At 10:30 am, we slowed our pace and had an early lunch since we could walk up and order, then tapped in for a 30 minute wait for another turn on Krakatau Aqua Coaster while we braved the float on the turbulent river.
My DD lost her Tapu Tapu on the turbulent river (I cannot recommend enough the Fastener Rings for the bands, from
Amazon, we also used these for our Disney Magic bands ). Here is the link to the set we purchased:
https://www.amazon.com/dp/B00OMUF202/ref=cm_sw_r_sms_awdb_O40QzbKBFVBG3
The reason, I think my DD still lost her Tapu Tapu, was that we were rushing and hadn't secured it good enough on her wrist even with the band and that river was really turbulent. But we walked over to a concierge booth in the back of the park and since I had linked her ticket with my ticket, when I added a credit card on the Universal Wallet, I just had to tap and they were able to locate her information and issue a new band (no walking back to a locker to retrieve her ticket).
By 12pm, we had rode everything (except the big plunge) and had re-done some of our favorites. By now the park was getting significantly more crowded and all the slides had wait times except for the 4 - tube slide in the back of the park with float for 2-riders (not remembering the name of it). So we left the park.
One of the things that I was prepared for based on early feedback was lack of signs/maps to tell you where to go, but that seems to have been corrected. I found a lot of signage directing you to the various slides and well placed map stations throughout the park. When we were lost and asked a team member, everyone gave good directions.
We came back on Thursday, the 31st. Got there at 8:10am and re-did some of our favorites. Again Oh'yah and Oh'no were the 1st slides that I saw change from Ride Now to having to tap in. The Aqua Coaster even with Ride Now, was also a bit of wait and quickly changed to having to tap in. By 9am, the park was more busy than that Tuesday but still not huge waits. The kids still refused to do the Ko'okiri body plunge but I decided to do it. It was awesome, though quite the climb to get there.
Hope this mini write up helps! Again, we had an awesome time there and it wouldn't have happened without the knowledge I got through this thread with a game plan of attack.