I am a great fan of the feature "not more than x email from one website". It can scope to what you need without spending too much time with one site. If you have the correct URL where to scrape you don't need to wait for unnecessary crawling all on the same site where everything is already grabbed.
I would like to do the same with phone numbers! Would be great to have this feature not only limited to emails!
Thank you in advance for delevoping!