I think/hope Disney learned something when they opened Pandora over Memorial Day weekend in 2017 at Animal Kingdom in Florida. I have written this elsewhere in this forum, but I was shocked at how well Disney handled that as far crowds. Wait times for the new rides were 5-6 hours. And wait times to even enter Pandora were an hour - yes, they restricted access to the new land. Only when people left would they allow new people in.
Also, Pandora does have some of the immersive elements you are talking about. CMs in character and trained beforehand. Translation booklets from English to Na'vi to guests. CMs ready to show you the local "Pandora" fauna. I think Pandora is about 12 acres vs. 14 for SWGE - so a similar scale. I just hope that Disney is smart enough to get that learning curve from Florida to California for SWGE because from what I have seen at DLR in recent years, they do not handle super large crowds very well from an organization standpoint. WDW nailed it for Pandora IMO.
As I recall for Pandora, they started doing CM previews in April and DVC and AP previews in late April and early May. I suspect that DLR's SWGE will make for longer queues than WDW's because of the AP effect at DLR. But with DAPs blocked most of the summer that will mitigate the APs. It is a year-and-half since Pandora opened and their signature ride, Flight of Passage, is still peaking at 4 hours wait times.