LoTR is more famous as a book series though than Wizard of Oz/Wicked. People think of the movies when they think of those IPs, whereas with LOTR the books are just as successful as the movies. So imo, I still 100% believe it belongs in IoA. It fits with the theming of the park perfectly and if you get rid of Toon Lagoon entirely (the entire land+the theater) that's a lot of space for one land. If it's a huge success, get rid of Kong and expand into that land. I completely disagree about Wicked not having enough material to justify that huge plot. There's a lot to work with there with that IP. Also, they could use half of that space for Wicked and maybe expand HTTYD with the other half. I doubt whatever new IP comes next to EU will use the entirety of that space. Having Hogwarts/HP, Legend of Zelda and LOTR in the same park would just be so perfect. It makes too much sense in my eyes.
As I said previously I don't really understand why you guys think one IP is taking that huge space. I mean it's certainly possible, but I don't know. I just have a feeling whatever goes in that huge plot will be multiple IPs (at least one new IP, expansion for HTTYD or celestial park, or maybe a 2nd new IP.) not just one huge land. I don't disagree with you about the popularity of LOTR. I know it's generational. If they want to build multiple lands for it if the first one is a success put one in each of the parks. I'm not against that. But for now if it does happen I think it should go to IoA to start.
Edit: I also just want to add, I agree that at some point LoTR will come to the parks. But I also see a possibility that it doesn't. What if it goes to Universal Studios UK as an exclusive? I feel like that park will 90% likely have a LoTR to start and they might want to keep it that way for a long time. That park specifically is going to need a huge draw that isn't tied to anything from the current parks and that would be the biggest one besides Wicked they could use for USB.