With the removal of a seasonal affix in season 2, Blizzard should remove the +2 IO for timing 11s and higher.

In the blue post announcing the addition score from 11s and higher, they claimed people would find the difficulty of KSM similar to that of SL.

With the removal of a seasonal affix, that added difficulty will likely not be there. It would also return KSM to needing an average of 15s and KSH needing to complete an average of all 20s.

I think there is also a discussion that could be had about whether or not S1 was really as difficult as SL seasons.