I've replaced this menu with a much simpler text only interface:
The first five options in the original Japanese menu each changed different parts of the game's text from English to Japanese. I've simplified this into a single option that converts all the text. The existing English version of the game, while still containing much of the original Japanese text in the ROM, does not have the option to display the Japanese text:
The menu looks better than mine, but is missing the English/Japanese option. I could have just copied over the menu from the English game, but it just feels weird to remove functionality from a game. Would it be better just to go this route? Japanese players already have an uncensored version of the game designed for them, so it wouldn't really prevent anybody from experiencing the game. I also looked at porting the uncensored content to the existing English version, but moving the graphics to make everything fit would result in a huge patch size. The final option would be to mimic the English menu but add the additional language option. This would probably look a little strange, as the font size would either have to be very small to fit within the boxes, or I would have to abbreviate "English" to "Eng." and "Japanese" to "Jap."
Note: I'm not removing the ability to change the background color, I just haven't added the text back in for it yet.