Upgrading my home server from an Odroid HC2

Hey folks. I've been running a media and torrenting server off an Odroid HC2 running OpenMediaVault 6 on Armbian. It's been doing pretty great, and I have it set to run docker containers for qBittorrent, ProtonVPN, the *arrs, etc.

The problem I'm running into is that the HC2 has an arm32 CPU that is not supported by most apps, so I'm stuck running old images. I want to upgrade to a newer mini PC/SBC that is more future-friendly. I'd like it to be capable of running Plex streaming at 4K, Radarr/Sonarr/Prowlarr, etc. as well as other apps as docker containers. I might repurpose the HC2 to just run self-hosted NextDNS.

Here are my questions:

1. What mini PCs or SBCs would you recommend? I'm leaning strongly towards a mini PC over an SBC because it would be more powerful, I don't need specialized software for it, recovery and backups are much easier, etc. I'm not too concerned about power usage unless it's extravagant.
2. Which OS would you recommend as a media server?
3. What is the simplest way to transfer my server over with minimal fuss? I use private trackers, so I'll have to very carefully stand up the new server and transfer over torrents, etc. in one fell swoop. I'm guessing I should just be able to install the apps and then transfer over the configurations and media files and change permissions, etc.
4. Anything else I need to consider?

Thanks!