I use docker and docker-compose.yml files for all my services under a docker user that doesn't do anything else. I use
linuxserver.io docker containers as everything is consistent between the docker setup. To update I just run 'docker-compose pull && docker-compose up -d". Each compose file is set within it's own folder where the config and other program data is stored on my SSD array. Then all of my media files are stored on my ZFS share located within mnt with a proper hierarchy. /mnt/zfs/media/tv shows/showname/season/episode
I rarely have an issue with any of my docker containers. I backup the directories that are stored on my SSD array to my ZFS share that has been alive for over 10 years now. If I reinstall Debian or install another distro on my server I just restore my docker-compose.yml with the config data, pull and start the docker. Takes a hour or so to get everything back running nice and smooth. I've had RHEL, Debian, Alpine, openSUSE, various VMs run my ZFS shares and docker containers. I started with Debian and finally ended up with Debian for my server.
I used to use usenet for sonarr/radarr/jellyfin with great luck. Torrents suck comparatively. I don't watch anime so don't know much about it with these services, there is probably a dedicated anime *arr program out there.
If you want to watch you media on the go though. I would strongly suggest not opening up random ports to the outside. I would go with a reverse proxy solution with cloudflare argo tunnels or by setting up wireguard/openvpn then connecting to the VPN to manage your home server and services.
Nowadays I use Kodi with the Fen addon, syncing my watch data to trakt.tv and jellyfin. This requires a debrid subscription, costs $4 a month, but I can watch 1080p movies or tv shows on the fly and don't need to upgrade my 32tb server for more storage which is getting close to being full. I still download movies/tv shows that I rewatch from time to time. Fen will pull from my local ZFS share before searching for external sources.
For my HTPC setup, I have an old thinkpad that is docked. Running Arch built with the default archinstall script, with plasma selected as my inital DE and
plasma-bigscreen as my DE which is perfect for a TV. Use a mini keyboard to navigate, then use firefox with ublock/sponsorblock to watch youtube/rumble/odysee. Play games with
moonlight-qt which allows me to remote play from my desktop on my TV.
Emulation Station-DE is my default app for managing my games to play, works well with a controller, and works with Lutris, Steam, and emulated systems.
After using a Raspberry PI 4 I had lying around for Kodi, it was rough and slow. The laptop can handle so much more and cost me 40 bucks which included a 500gb SSD (has a broken screen and I had an old dock lying around), much cheaper than a RPI. It is much more versatile as there was no RPI solution that could handle what I wanted. A NUC, old Optiplex, or something similar would do just fine as well for a HTPC.