Well I won't be playing it 'til the game comes out because Nintendo hates my country!
But more seriously, I get what you mean - sometimes, praise can feel tedious, like you're getting too much credit and you would rather hear some criticism so you can improve.
But really, not many people outside of Nintendo would have played Rosalina as much as you, because most people were interested in the Super Fighting Robot, the cool boxer, or the ninja Pokémon. Nobody was hyped for the space goddess.
I think you're analysis is reliable. While it makes Rosalina sound like she will be one of the best characters in the history of the franchise, that's not necessarily poor analysis, it might just be the case. Maybe if you had this sort of time with Meta Knight before Brawl came out, for instance, you would have been able to call him out on his OP status before the game was even out.