What email marketing cloud services are there?

Question

Email Marketing

Hello, I plan to collect a subscription database of email addresses and conduct a white thematic mailing list (not spam - a double opt-in list).

In general, I have little experience and a basic understanding of how it works. Register on the mailing service, set up a subscription form. a chain of letters, etc. But in this case, I see some minus for myself, namely, the relative dependence on this mailing service - from moderation of letters to a ban and loss of the base, possible problems of migration to another service, etc. + prices.

I see a way out of this to raise my mailing service, using scripts like Sandy, MailWizz, AMS, etc. on your server and send via smtp. All this requires: a. buy a script; b. set up correctly.

The question is whether there is an intermediate link in this scheme, some kind of cloud-based ready-made mailing and email marketing system with a sane monthly payment, which provides the necessary functionality for mailings, but is not an email delivery provider itself and does not require compliance with a spam policy, i.e. the system is theirs, but smtp needs its own (Conditional cloud MailWizz)?