UltraSeedBox does pretty much everything you mentioned. They even have Emby and Jellyfin as stream server options as well, all with GPU power for even more efficient transcode ability.

Their systems have rclone mounts enabled for streaming from gdrive and a great community on discord to help with setting it up if you're not familiar with ssh (coding as you referred to it lol) Their knowledge base guides are excellent to get anyone, even n00bies going.

They are the go to standard for pretty much everything you mentioned, especially remote storage streaming, and so much more