I think having the “Add Paused” option for torrents added to Deluge on a per-show basis would be awesome
What does this mean? You mean you dont want sonarr to pick up anything added to the torrent client on a per show basis?
No, it’s an option in the settings of your download client in sonarr, to send torrents to your client, but in a paused state.
Since it’s a setting on download client, it applies to all series. OP wants it on series level.