so the problem here is if you have all of those needs, then really soon in the life of the project you are going to need good tooling to handle them.
So choosing something which makes it "one-click" to set up but total madness to manage is a really short-term optimization, only worth it for a pure prototype which you will throw away no matter how successful.
If you know you need those things to reach success, then it is better to make the up-front investment to get good tools for those.
If you still want to go with a cloud provider, AWS Amplify has some interesting tooling. I've build products both against Amplify and Firestore (and Firebase). Yes, Firebase is a few days to a week faster to set up (integrated user management, as you say), but AWS gives more sophisticated control and is built around scripted deployments.
You pay for it, of course, and I'm not arguing AWS vs running your own server. I am saying if the choice is AWS or Firebase, that a few days researching the choice would give you knowledge you could use for launching the next 10 prototypes you have in mind.