Sonarr/Radarr + Plex has been good enough for me.

I just hope that Lemmy.world performance improves over time as sometimes the performance is a bit jarring and something I'd find hard to recommend to less tech-minded friends swapping from Reddit

yeah they work great here's how I have mine setup

Sabznbd Prowlarr Sonarr Radarr Docker container for Flaresolverr https://github.com/FlareSolverr/FlareSolverr

Now if you want to go further than that you can setup profiles https://trash-guides.info/ for quality.

But the truth is the problem isn't Sonarr or Radarr it's just that Torrents can be kind of garbage with automation, I would suggest you look into Usenet. It costs a bit of money to spend but a much more consistent experience.