Too expensive to be worth it. I'm totally fine with outsourcing stuff that is difficult and third parties can do better, but in this case the amount of stuff you're playing egregious "cloud" pricing for is too much. Just spend a handful of days learning one of the open source stacks and you'll be set for life. It's totally worth it assuming you'll be making more than 1 app ever.
Firebase's free tier is more than enough to play with an idea, and the next tier up is (100k concurrent users) $25/month ... if that's too expensive then there's something very wrong with your pricing model. Obviously this assumes you're not storing much data per user - you wouldn't build a imgur clone with it - but it's not that expensive for any typical SaaS app.
Concurrent users are not the only limitation. Your app needs to fit the bandwith limits as well. I had to shutdown a very simple app with a few users because of ridiculous billing.
For me, time I’m writing unnecessary code or learning libraries I don’t already know is time I’m not spending thinking about the product. I’m a designer who just wants to ship.
I am open to suggestions though. What would you recommend for, say, auth instead? I’ve tried rails, Django, node/mongo, etc; even hosting a small db on compose.io comes with a chunky base fee, and I still have to do way too much work for user accounts/search/APIs/ORM. There’s a reason Firebase is popular with the yoof.