I recently sent them an email about a thing I really find frustrating at HN:

Hi all,

I use a lot HN a lot and too often I receive this error:

You're submitting too fast. Please slow down. Thanks.

The most frustrating part is that I receive it after I submit the link, wouldn't be elegant to have a status icon or label that would signal that my account status is available for submitting. This way I will not submit stories in vain

  Thanks,

Ed

and got no answer.