My favorites are:
-Forbidden Journey (as a HUGE HP fan, my fave ride ever, anywhere! Rode it 10 times last trip!)
-Escape from Gringotts
-Mummy
I know a lot of people can’t handle Forbidden Journey, but if you love HP, you owe it to yourself to try it. For me, I do better if I do it on a full stomach and briefly close my eyes on the transition immediately after the (SPOILER ALERT!)…
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…Whomping Willow, leading into the Quidditch match. For me, that part is the worst.
All the headliners people above have suggested are favorites. But one “hidden gem” is the Horror Make Up show. It is a HOOT! Don’t miss it. You won’t regret it.
I want to like FJ but I just don’t. I find the transitions between filmed scenes and physical scenes really jarring visually. I have to close my eyes during the Aragog scene as I’m an arachnophobe.
I’ll still ride it once a trip but only once.
I understand this, and I know many people feel this way, but for me, it’s not at all problematic and I find it amazing! 
LOL! Me, too! And last time ride stopped and I was stuck right in front of one of those spiders! SOOO much worse than the motion sickness!
And I thought the combination of 3-D time, physical attraction time and motion through the castle made this one of the best technological rids I’ve ever been on. But my daughter (age 24) did get motion sickness both times we rode.