Sadly, $900 for one night and express pass is not in the budget for many travelers, myself included. No matter how great it might be, if it’s too expensive, then it’s too expensive.
The week before Easter will definitely be really crowded, but that doesn’t condemn you to super long lines all day, unless you are only going for a day or two and trying to cram everything in.
Your multiple day idea is the best, so be there right at rope drop. You will not have the onsite advantage of early park admission, but you can still rope drop. Because only a select few rides are open during EPA, one strategy is to be at the front of the regular-opening pack, and go elsewhere. Velocicoaster and the Harry Potter parts of IoA will be mobbed, so turn left and rope drop Hulk instead. In US, there will be a huge line at Gringotts, so head to Rip Ride Rocket, which is usually not running during EPA.
You can probably get in a few rides before the lines get really insane. Then watch the shows and take in the atmosphere. The shops can be well-themed and worth looking, even if you aren’t buying. There are some great play areas, too. Also consider having a sit-down lunch in the parks. Maybe make reservations at Mythos to get you into the AC and out of lines.
When the lines and the crowds are unbearable, take a break. Go back and swim at your resort or chill in your room or do another area attraction. The lines should drop a bit towards the end of the night, and UO is typically open late on holiday weeks, so go back and grab a few night rides. This is easier to do if you e had a siesta. Then do the same for another day or two. You should be able to get through it all if you’re flexible and take it in chunks.
Another tip - bring games to play in line. We have even been known to download Universal movies, and watch when standing in the queues. Don’t forget charged phones and perhaps an external battery pack to recharge.