Common features open source options

I have the same problem and all the SaaS tools for it in my view a too expensive. In the end, I spent two months building a bunch of serverless functions to do that (They pretty much use only the free tier of AWS services, so, cheap). Of course, they need some customization for a few projects but they are very flexible at the point I can use across several projects. I'm planning on releasing them open source at some point, but so fat didn't get the time for it.

Another thing is to use some "Hackathon/Startup Start Kit". Something like these https://dev.to/sm0ke/nodejs-starter-javascript-boilerplates-to-start-fast-1024 They are pretty useful and very flexible. Usually, the performance is really bad, but for a new app without market-fit, in my opinion, they can speed up things.

Node developer here. JavaScript ecosystem moves so fast so it is quite rare to have something that Rails does.

I went through the same process as yours and began looking at Rails/Python/Elixir. I did enjoy Elixir + Phoenix, but I found that just using my JavaScript/NodeJS existing skills and to build it is faster than to learn other ecosystems. Especially that you can share your code from frontend, backend, desktop (Electron) and mobile (React Native). (that being said, I use Rust as my backend now)

I think for users and payments I find that Auth0 and Braintree/Stripe works fine. Easy to implement, no hassle

Node is kinda rough for an indie. There's a lot to implement and not many batteries included. Though I worked with it for years as an employee, I moved on to Rails and then Phoenix, both of which were a lot more productive. That said, one decent Node MVC I used in the past was SailsJS.

I've seen a number of people here selling Node SaaS templates and maybe one of those could help.

Great question.
How about Firebase?