It would be nice to have a reset button. Sometimes I get stuck in the first 10 numbers and it's obvious I'll get an horrible time, so I'd like to start again immediately.
Edit: Perhaps after some time like 1.5 seconds, highlight the next number so it's easier to find. I will not help too much to get a record, but it will reduce how annoying is to get stuck.
I think that 4 seconds is too much time. I'm now at 18.78 now (with a touchpad). That's slightly faster than 1 per second. Looking at other comments here, they are at almost 2 per second. So a 2 seconds pause is probably enough. You should test it with a few friends.
It would be nice to have a reset button. Sometimes I get stuck in the first 10 numbers and it's obvious I'll get an horrible time, so I'd like to start again immediately.
Edit: Perhaps after some time like 1.5 seconds, highlight the next number so it's easier to find. I will not help too much to get a record, but it will reduce how annoying is to get stuck.