How to fix FPS dropping from 70 to 30 in dense areas like Rattay?

I was so excited for this masterpiece, but the joy faded when I entered Rattay and saw my FPS plummet from 70 to 30. I tried the Windows High Performance power plan, which raised clock speeds but didn't stop the drops; the trial-and-error was torture. I used the GamePP Process Priority Manager to set the game to Realtime and activated Memory Acceleration mode. RTSS monitoring showed frame times converged from 18-35ms down to a smooth 14-18ms, while GamePP noted bandwidth at 65-88%.