Good thing we have competitive (and cheaper) options now including Digitalocean app platform and Render.com. I'm actually surprised it took this long to match Heroku (and beat them on costs).
Heroku, on the other hand has been a hassle-free solution for my company over the past 7 years, and short of a few outages (which were actually the fault of AWS from what I remember), it has been absolutely reliable.
We've worked hard to incorporate reliability lessons learned from building the platform at scale especially as we've grown [1], and I hope you'll give us another chance. If I can do anything else to help, my email is my HN handle at render.com.
[1] https://www.tfir.io/more-than-100000-services-created-on-zer...