I didn’t see this mentioned so apologies if this is a duplicate, but keep in mind that for your *arr stack you will run into issues if you try to keep the config files on the NAS instead of stored locally to the server they run on. Radarr and Sonarr both use sqlite which does NOT like networked file storage due to the way it handles locking files.
You can store the media that they handle on your new NAS just fine though!
I didn’t see this mentioned so apologies if this is a duplicate, but keep in mind that for your *arr stack you will run into issues if you try to keep the config files on the NAS instead of stored locally to the server they run on. Radarr and Sonarr both use sqlite which does NOT like networked file storage due to the way it handles locking files. You can store the media that they handle on your new NAS just fine though!