If you live on the other side of the world, filtering by date is an issue. If you connect from Asia and with most of the activity on HN coming from the US, there is little to see during our mornings. I expect to see what I have missed on the last 24 hours without have to change the date manually.

Perhaps you can show a the top 10 (or 20, or xx) of the previous day with visual separation so that I know if was submitted earlier.

I think Up/Down would be better.