The paper styling of the characters in this game is very clearly a touched-up version of the original version, unlike the two previous games which are more in line with the first Paper Mario game. I wonder if they are planning to use this style going forward. Certainly invites a lot of flexibility.
On the other hand, the environment of this game is very much in-line with the HD Paper Mario games, which I think is fine because they look fantastic, and didn't fix what isn't broken. So if you compare these Petal Meadows environments, you can see the more papery look in the HD version (bottom) as opposed to original version (top) that didn't depict much of it as papery, like the grass. Which I think it's appropriate, since this game is the first one that plays the papery aspect more ambitiously (Hooktail is the biggest showcase, I feel).
Also, I think the game benefits immensely from a grander instrumental because it just fits the themes better. I was impressed by the battle theme as opposed to the original, so the new themes will certainly be a highlight because it's certain to improve from the original.
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Unrelated to the HD version, but for the game: There is something I find a bit curious. We know that the story of the game involves a big threat that is not Bowser, yet Bowser this time only features in the interludes until the end. I wonder if the developers didn't intend for Bowser to be in the story, but only included him because they were told to get the memo? Because in the major scheme of things, I believe he's only role in the main story is as a distraction before the final boss.
Thank you for reading.