In my opinion, one of your biggest problem in acquiring customers is that the gatekeepers out there, the big name bloggers, have a vested interest in continuing to send their readers to Aweber, ConvertKit, MailChimp, etc. The kickbacks they get are huge.
As a specific example, go to smartpassiveincome.com and look at his monthly income numbers, and how much he is getting from ConvertKit (a few years ago it was Aweber). Those affiliate commissions alone are a solid six figure income.
The end result is that he has no incentive to push a basic mailing list management solution that satisfies 99% of his readers' needs. Instead he has a great incentive to push the narrative that his readers need this overkill solution for when they launch their million-dollar course in 3 months. (I actually like Pat, or at least his internet personality, so no offense to him, this is just how human nature works)
Not to mention the strong pull on the customers' parts to feel like pros by using software the pros use, even though they don't need any of the features or support they are paying for.
I never came up with a satisfying solution around this. The best idea I had was to cultivate a brand as a rebel in the space, pushing back against this "evil conspiracy" by passing the cost savings directly to you.
P.S., you guys really need double opt-in. I believe it is legally required in many places.