Alright, some good news. I have the game working unpacked, which I wasn't able to do before, with fully integrated DLC. It will take me some time to get everything done translation wise. IIRC there was a lot of manual cleanup I needed to do for Excel Chiffon because of the complexity of the code, and the DLC added a lot of new content.
Vague news, the game is 8GB unpacked, which is a lot. I am still not sure what the mode2 and mode3 folders do, but it seems like they duplicate all of the basic sprites at higher resolutions. Might play around with those and see what happens when I remove them.
The bad news, fuck the devs, man, this is so obnoxious. They upscaled the game from 1360x765 to 1366x768 requiring me to remake all of the background images with hardcoded Japanese in them. Stg they did this just to piss me off.