I would think that if both Roshar and Scadrial have pure tones, the other planets in the cosmere would as well. Singers, the natives on Roshar can hear the Rhythms because they are attuned to them. Since seons could count as the native to Sel (them being slivers and all) it would make sense that they could attune to the rhythms of Sel.
I just counted all books that Brandon Sanderson has written including novellas, all 5 secret projects, Aether of Night, Way of Kings Prime, and books coming out this year. It totaled 59 books! That's insane
Sp 5 also, it's just not published. And Dawnshard. I forgot about the first two you listed! That's 14 then. And Lux adds another to the fill count bringing it to 60!!!!!
This seems the most likely.
I would agree with this.
I'm hoping for either Secret History 2 or Mistborn movie, although that last one seems not so likely.
I would pick F-nicrosil and Bio-chromatic breath. You could store your breaths so that people couldn't tell how much you had, and then draw on them at any time.