In terms of immersion, Hollywood Studios. There are no "exposed steel" rides that break the sense of being transported (SDD is auto-themed, even if weakly so), and the slightlines are vastly superior. And of course, the Hollywood areas and Galaxy's Edge are some of the best most transportive environments in any theme park.
In terms of attraction lineup, Islands of Adventure. Despite Tower of Terror and Rise of the Resistance
arguably being superior to any of the attractions at IoA - and ST, SDD, MMRR, RnRC, TSMM, etc. being great fun - they don't make for a lineup of this caliber:
- The Amazing Adventures of Spiderman
- Harry Potter and the Forbidden Journey
- Hagrid's Magical Creatures Motorbike Adventure
- Velocicoaster
- Popeye and Bluto's
- Jurassic Park River Adventure
- Ripsaw Falls
- The Incredible Hulk