Leap seconds aren't needed at all. I'd rather let them accumulate until there's a leap hour that can be rolled into DST (although DST may not exist that far in the future).
I.e. gradually slow/accelerate time over the course of a day, rather than stepping it hard at once.
I'd say this approach would be vastly preferable for about 100% of the systems relying on pool.ntp.org.
The remaining 0%, e.g. scientific applications that absolutely need the leap second to appear at exactly the right moment, most likely don't use pool.ntp.org anyways.
And for those who do they could create a second pool with the old behavior. Maybe call it science.ntp.org.
When you look at how much people crap their pants over the leap second - a relatively common thing - I dread to think how unprepared people would be for something 3,600 times less common.