So do you think there's a chance this turns out better than if they had used the movie's story? Or is at best equal? Can this really exceed what could have been with the movie's story?
I think there's every chance in the world it turns out as good as or better than if they did a book report style ride. The fact of the matter is we know next to nothing about the story or what's inside that mountain. People are running wild with speculation based on nothing but simple backstory that will likely not factor in a whole lot to the attraction itself, just like all the other attractions around the world with large and detailed backstories don't really factor in that much to the ride experience.
And I don't meant the following as being directed toward you, I want to be clear, this is just a general statement.
The hair splitting over things like would or wouldn't Tiana venture into food wholesaling, fonts on a sign, and all of this other nonsense stems from nothing but a large swath of people who just refuse to believe that this do-over is not some personal attack on them and their childhood. Splash Mountain was iconic and had it's time, but we all saw as time went on that the attraction was no longer running at it's best, not to mention there was very little engagement with it from an audience perspective beyond "oh fun flume ride."
Whether Disney park die hards want to admit it or not, the vast majority of guests that come to Disney parks want to come and engage with their favorite Disney characters in some form or fashion. Princess and the Frog is a popular film and Tiana is a popular character that just so happens to mean a hell of a lot to a swath of young girls who don't very often get to see somebody like them be treated like a Disney princess.
At the end of the day, it's a ride. It's not that deep. Especially not when it's the exact same ride it has been since day one, just with different characters that the vast majority of people actually care about within it.
It's okay to have liked Splash and to miss it. I'll miss it too. But a huge group of individuals really need to look deeply within and ask why exactly they're taking this so seriously and why there is a need for an online crusade against a re-theme of a 35 year old log flume.