What are indie hackers looking for in a newsleter delivery service?

I'm currently building an app and was going to publish a landing page that explains the basic idea to people & let's them sign up for a newsletter to be notified when the app launches. And that's when I realized something:

Newsletter services are h***ing complicated!

Having looked at most SaaS-style newsletter delivery services, most of them seem to be targeting companies that have fulltime (eMail-)marketing departments. They offer every stat imaginable, every specialized service under the sun & have a UI that makes you drown in buttons, charts & possibilities. None of them make it easy to create, integrate & launch a simple & small newsletter.

So I'm wondering: What do you, the indie hackers of this world, look for in a newsletter delivery service? Is simply having a site that generates an embeddable signup form for you & lets you send simple eMails with a sleek template enough, or do you actually need some of these super advanced features that are on offer with those other services?

(Obviously, I'm now thinking of building a simplified newsletter & waiting list style service for smaller businesses & indie hackers myself, which is why I'm asking these questions :) )