You can waste you hdd space, then you need to clear it and delete some torrents. But torrent history is a good practice, you can suggest something to you friend or watch it again, but you cant do it with qbittorent. Now I open download folder, delete files, qbittorrent gives error, but it works. I use QBT for ~3-5 years, as I remember, BitComet has it, after delete it moves torrent to history
Another problem you cant note torrent for youself, for example 'Vovan will like it/it has very interesting moments in 1:13:18'.
You can do it useing sites/notepad/word/whatever, but simple notes without much clicks is good