Piracy: ꜱᴀɪʟ ᴛʜᴇ ʜɪɢʜ ꜱᴇᴀꜱ

I have a collection of about ~110 4K Blu-Ray movies that I've ripped and I want to take the time to compress and store them for use on a future Jellyfin server.

I know some very basics about ffmpeg and general codec information, but I have a very specific set of goals in mind I'm hoping someone could point me in the right direction with:

1. Smaller file size (obviously)
2. Image quality good enough that I cannot spot the difference, even on a high-end TV or projector
3. Preserved audio
4. Preserved HDR metadata

In a perfect world, I would love to be able to convert the proprietary HDR into an open standard, and the Dolby Atmos audio into an open standard, but a good compromise is this.

Assuming that I have the hardware necessary to do the initial encoding, and my server will be powerful enough for transcoding in that format, any tips or pointers?