I had this idea when I was trying to double-S-rank a song: there could be a 1,00x mod (like Sudden Death) that you could customize how will you fail, either by missing a note, scoring a 50 or 100 or any set amount of them, or whatever. This could be not only useful when trying to achieve higher scores but also in multiplayer, as an "insanely insane/Saturos" mode of sorts.
It could also be called "Custom Sudden Death" (or SD for short).
It could also be called "Custom Sudden Death" (or SD for short).