We'd still need a way to specify the sort order, but also indicate that the output does not have to be sorted. (e.g. introselect)

For example:
Input is [4,1,3,2] N is 3
topN/bottomN with sortBy 1/-1 can return [4, 3, 2] [2, 3, 4] [1, 2, 3] [3, 2, 1]
This ticket suggests letting the user return e.g.
[1, 3, 2]
without having sort the result.