Just a note, we were there on Sunday and thankfully bought the Express Pass because the Insidious house was a two and a half hour wait. We thought the worst house was Run. Also long waits at Walking Dead and Purge each almost reaching the 100 minute by the middle of the night. So it would depend upon what time you get there.
We stayed on site and so we had the onsite line up and we were about the 4th people through the gates at 6 PM when they opened. We went straight to 25 years, did American Werewolf, then Freddy vs Jason and then Body Collectors. The wait was 5-15 minutes for each house. By 7 PM we were getting a drink having done 4 houses. From 7 PM on the minimum wait for any house was 30 minutes with the popular ones now at 60 minutes by 8 PM the most popular (Insidious, Walking Dead, Jack Presents and The Purge were all over 100 minutes. Get there early!!!! 5 PM....We got there at 5:30 PM and the line for the regular guest at the main gate looked to be about 100 people or more deep, it stretched out of the gates about 20 feet from the Universal Globe. You will have to go through metal detectors which only a certain amount of people will clear before they open the gates around 6 PM. If you get stuck waiting to get through those you may as well have a drink at NBC and wait an hour until the first surge gets through. Officially HHN begins at 6:30 unofficially they let guest in as early at 6 PM. When you see the fireworks, the gates have been opened.
Do see Bill and Ted's and The carnage Returns, both shows are excellent.
Get a map and check out where the houses EXIT so you don't have to do a lot of backtracking.
There are the pop up bars everywhere but the pop up HHN food tents aren't everywhere, we walked around the whole park and found biggest concentration of the food tents were in the NY area, and then one over between London and Men in Black, and one over by ET area (that one had cheesesteaks.)
I did not wear the 3D glasses in Asylum in Wonderland, just putting them on as I first entered a room and then took them off, buy the end of the house I did not wear them at all. They just made all of the lights blurry and psychedelic looking.