I’m not sure if they’re still affordable but I ended up getting both a morefine and a beelink, one with the n100 Intel CPU and the other with the n305. They handle everything I’ve thrown at them, and come with out of the box quicksync transcoding for Jellyfin/Plex. Handles 4K transcode like a champ. Couple that with 2.5g Ethernet and they sip power. Though they might have gone up in price since I bought mine.

Seconded ytdl-sub, especially if you want them to work flawlessly with Kodi/Plex/Jellyfin (integrated into the library etc) Other than that, tubesync is nice and has a decent web ui too.

I’ve got a morefine m9 with an n100 in it, it handles nextcloud, immich, paperless, and much more without breaking a sweat. I also chanced throwing 32gb in it and it runs fine.

I’ve got a beelink eq12 pro too with an n305 in it, and it handles all my plex transcoding etc. Doesn’t handle 32gb ram though unfortunately!

Both are very power friendly and work great with HDDs connected through external yottmaster enclosures through USB.