You can also sometimes find a short Hagrids line in the early afternoon (lunch time & such). Unless you are near the front of early entry, avoid getting in the Hagrids line in the morning as that is generally the longest wait of the day. Early entry can be a great time for short waits on not-Hagrids.
The last few hours before park close will have shorter waits on most rides. Take a break mid-day (go back to the hotel, or just a leisurely meal in AC and/or a few shows) to be able to take advantage of those last few hours. The buses are very efficient if you do decide to go back to the hotel. It's much nicer than pushing through the afternoon heat/crowds but then petering out a few hours before close & missing the nice short evening waits.
Pretty likely that Thurs & Fri will be the start of
HHN. Expect Studios to close early (5pm) but Islands to stay open a little later. There can be short waits 3-5pm in Studios but some walkways may start to be detoured around HHN holding areas. The Hogwarts Express line becomes crazy long in the afternoon.
If they're doing a Hogwarts light show when you're there, don't fight the crowds to see the first showing or two. The later showings are MUCH less crowded and they normally keep going right until or past closing.
The Bourne Stuntacular is not to be missed, plus it's a nice long AC break. The Horror Makeup show is also good - witty, sit down, and AC.
Depending on the ages of your travel party, single rider lines can be very effective although you miss any pre shows. Except for Rip Ride Rocket which has a very slow single rider line, and Velocicoaster which also can be slow, the rest are pretty efficient.
The Universal App is great for showing wait times and show times, and the map, mobile order, etc.
Jurassic Park River Adventure will get you wet but very rarely soaked. The other 2 water rides, Popeyes Barges & Dudley Dooright flume, WILL get you thoroughly soaked. They are a lot of fun as long as you are prepared for a drenching.