Were we just viewing the series though nostalgia goggles or is there actually something very wrong?

I got bored farming Battlespheres for XP, so decided to try NewGame+. Everything transferred EXCEPT what mattered most to me, Sora's level. I would have had more fun playing the actual game to try for the max level, but it appears I can not do this. So is NewGame+ irrevalent to me?...

So what exactly happened? I felt like I missed a lot of context. Sora goes to find Kairi, then the plot skips over that chapter, jumping immediately to Namine's awakening. Since Namine is part of Kairi, I was confused how she could be reborn without her presence. I think there's a lot missing there, does this absent chapter exist anywhere?...

I just go to the part where Ventus opens up a can of hurt on Vanitus and then Kairi talks about a pending "final battle" According to the achievement list, there is one for getting Sora to Level99. I am somewhere in the mid-40s. So as I've just finished the final Disney world, how much more of the game is there to play through? I doubt there's enough gameplay for another 50levels worth of XP...........

I wanted to love this game but was shocked you could not remap the keybinds. For a lefty who has gamed on PC for years I have a preferred way to map things. Very odd they dont allow it.