I think the lack of Naveen was the most surprising element to me since he was the co-lead of the movie.
One of the YouTube reviews I saw of Tiana's Bayou Adventure, that had a mixed-leaning positive review of the ride, noted that most Disney rides tend to recreate the iconography of their films — even if the rides are technically set after the film like in Frozen Ever After. He noted one thing that might disappoint Princess and the Frog fans is how TIana's Bayou Adventure feels very disconnected from what people remember about the movie. Naveen is hardly in it. There's no epic "transformation" scene where Tiana and Naveen kiss and revert to human form. Tiana doesn't wear her iconic blue or green dresses and is seen sporting an Indiana Jones/Lara Croft/Jungle Cruise-type adventure outfit with a new haircut. Dr. Facillier and the shadow demons are completely gone. Ray is gone and any overt references to Evangeline. Overall it just feels very very loosely connected to the Princess and the Frog.
I've gone through the stages of grief already in terms of realizing the new ride isn't what I wanted it to be. I hope Disney makes improvements to it later down the line (more animatronics, more Naveen, some thrill elements, etc.) but if the ride remains as is it's a perfectly decent attraction. It just doesn't compare at all to what came before, despite the Princess and the Frog IP having the potential to create a ride that was better than Splash.
Maybe if the Tiana movie/series that's in the works ever comes out and is more tied to the iconography of the ride, the creative decisions made in Tiana's Bayou Adventure might make more sense and be less baffling in retrospect.