Hello
Enhance allows to limit mail sending rate, it is a good peace of security and will help you a little to avoid the blacklists. But rate limiting is possible only by sender's IP, I believe it is not very accurate way, for example, if you have a 2 customers with 2 different IP addresses, one has 5 emails and another 505 email, limiting the sending rate by IP will just not work. Don't you think that the limit should be based on sending account?
Dmitri.