READY PLAYER ONE feels like it would belong in the Studios if it were to ever show up, anyway.
I agree with this. This could replace Shrek, Fear Factor, the animal show, etc., I feel like it could literally go anywhere in the park aside from Diagon.
And I would argue, people shouldn't think of it strictly as a "Ready Player One" ride. Think of it as an opportunity for Universal to get super nostalgic... think of this similar to the Hanna Barbera ride. Have multiple vehicles, all Universal properties: DeLorean from BTTF (featured in RPO), KITT from Knight Rider (NBC, also featured in RPO), and Echo-1 from Ghost Busters. If you want a fourth vehicle they could likely negotiate the rights to The Mystery Machine (Scooby-Doo) or Bumblebee (Transformers).
The ride itself would be a no-brainer: base it off the first challenge from the movie (the race), but with tons of additions. Yes have Kong and a T-Rex attacking you for two easy Universal references, but you could also have Jaws and The Mummy. Have The Blues Brothers, Fallon, the F&F crew, Bourne, and Mario racing against you. Also include scenes which reference Disaster/Earthquake, Twister, Back-Draft, Water World, BTTF, and any other ride/movie I'm missing.
I'm not just saying this because I would 'love to see it', I honestly think it would be a great idea for a ride which people would thoroughly enjoy. Now whether Warner Bros (who produced/distributed RPO) would allow for Universal to have the rights to their movie, just so they can advertise themselves in it... that's a different story. (It would be nice if WB saw this as an opportunity to advertise their own IPs, but they'd probably just want more money for every IP used.)
Side note: Can I just tell everyone how hard it is to search for "ready player one" on these forums, since many refer to it as RPO? The search box does not allow for searches with only three characters.