Perhaps there's a Cave Story mod out there that does exactly that? It's a shame that Cave Story modding hasn't advanced enough that you can fight multiple bosses at once. Then again, I wonder if the Ballos fight was always planned or if it was added in late in development?I don't think you were ever meant to fight Misery in the original, it may have gone straight to the final Puu fight after the balcony.
The final puu fight honestly looks really fun, I wish Pixel would've kept it in the final game as a final balrog fight before or after misery.
NG+ really could've been the actual game mode itself if that weren't the case. Like, everything was more balanced out as a result, I thought.I understand how he feels. When people called my game piss easy during development I said fuck it and delayed it a month just to add a New Game + to it.