Mass mailing tool

Hello, on a daily basis I use an advanced web service for mailing, but now I need a simpler tool, but for a larger number of e-mails (database of between 1 and 3 million records). It is certainly necessary to freely change the domain from which the e-mails are sent, setting the interval between e-mails in milliseconds. The matter of text editing to be determined. Management of returns (bounced, can not be delivered, etc.).

I look forward to proposals from people who know the subject of mailing. Please do not send stiff offers, without any idea of implementation.

Greetings!