I add the song to my music and then put it in a playlist especially given I tend to like to hit random on My Music and play whatever is in there. I also tend to forget that I want to put a song in a playlist until later so My Music comes in handy for me anyway
I mostly jsut make playlist, a lot of which are private because some of them are just all over the place!
I never listen to "My Music", i just listen to the playlists I made. The only way I can see that saving songs to your library would be of any use is maybe spotify can recommend better songs for your taste. I only save songs from my favorite bands. I have a "stuff to listen to later" playlist so if a hear a song i like i can find it again but its not in my library.
I also use spotify on my phone a lot and I think playlists are the smoothest on mobile so that's another reason I just build playlists.
You can make a playlist called "Pending" (I call mine Routine). Here I put all songs I listen which I can't easily categorize. I enjoy having my playlists for classified per genre. From time to time I listen to my "Routine" playlist, each song of the playlist that gets categorized in another genre playlist gets deleted from the "Routine" Playlist
I don't use My Music as often as my playlist and other curated playlists by my favourite musicians, 90% of the time I go to My Music because I want to listen to an entire album and the remaining 10% is probably some cleaning after accidentally clicked "+" button or when I add songs fast (especially when I was driving I use Shazam or found a favourite track from another playlist).
It depends. I save the track if im interested in that album yet it is still to grow on me. In that case I save it because im afraid i will forget the title and decide i am going to do with it later
I also put certain music in my playlist, but usually for my workout exclusive playlist. In this case, not all music that I save are perfect for my workout. The ones that are will be put in that playlist