I hadn’t given much thought to the familiarity aspect, which could absolutely play a part. Still, I think what I bolded in your response says it all.
Na’Vi is very expensive and impressive, but at the end of the ride there’s this feeling that we didn’t do or see much, despite being bombarded with visuals for almost five minutes. Frozen doesn’t share that problem, despite having a lot less to look at, because it has a stronger focus that guides the audience where to look.
To bring it back to Mickey, I hope that focus shines through in all of the madcap antics, and that we’re about to get the E-Ticket version of Mr. Toad.