Hi If you still want to see either of the HP worlds I would do them first if you go to the park when it opens. If you don't get there when it opens and you peek in and it is busy I would go back later in the evening to check it out. It slows down an hour or two before closing. I am a HP fan so I think the rides are cool.
July is a busy time but with 3 days you can do what you want. Outside of the HP worlds. Minion Mayhem in the studios always has a long line. I would do that first thing in the morning. If you have thrill seekers in your party I would suggest Rip Ride Rocket next, it is close to Minion Mayhem. I would continue with the Mummy then Transformers. These tend to be the most popular in the studios besides Gringotts in Diagon Alley. Jimmy Fallon if you want to do this ride I would grab a virtual line pass first thing in the morning. These tend to run out very early. The other rides in the studio you can try and put together a route that puts them closer together for walking. You can hit MIB, Simpsons and ET are together in an area.
When you go over to IOA I would start to the left with the Hulk then follow right in the circle going to Storm Force, Doctor Doom, Spiderman. If you want the water rides (some will soak you) you will be getting to them next (Dudley Do Right Ripsaw falls and Popeye raft ride). You go into the Jurassic area next where you will find Kong, the flyers and the Jurassic River Ride. If you follow the path you end up in Hogsmeade. If you go straight through to the other side then I would just follow it down till you get to the beginning of the park.
I like the way IOA is basically a circle and we start at one end (when not worrying about HP in the morning) and just go around the lagoon.
I just realized you said you are doing all the parks. If your are doing VB that is a must do one day early. I would be at the City Walk parking garage by 7:00 am to park and be on a bus. VB has a tendency in the summer to max out by 8:00 8:30 am they don't let people in after that. If you can't do the morning then I would wait till later in the day maybe about 5:00 to try. When you go into VB I would suggest the water coaster if it is open. If you like body slides in the volcano I would do them next. From there I would do the family raft rides Honu and Moana. These are the most popular rides in the park. VB gets really busy so if you have park to park tickets you could plan to leave around noon or so when it gets busy and head to one of the other parks. When we went twice last summer we bought the express pass for VB so we stayed the whole day. This year if we don't get the express pass we will do VB in half day shifts. I would not stay there in the summer all day without it if you are a commando family. If you want a relaxing day and you get on the rides you get on then VB is good for that.
I would search up the Volcano Bay threads on here and read them for more tips. If you have any other questions please ask. Enjoy your trip!