I just led a migration for my small team from Zeit Now to Render (https://render.com/). It has filled this need pretty well. There are some features that I wish existed but overall the simplicity has been great for our use case. They do not have auto-scaling but it's planned (https://feedback.render.com/features/p/autoscaling).
(Render founder) Glad to hear it, and I hope you've posted your feature requests on https://feedback.render.com. We're investing heavily in growing the team and putting a strong engineering foundation in place so we can keep adding new features quickly and reliably.
Render is more flexible than Heroku: you can host apps that rely on disks (like Elasticsearch and MySQL), private services, cron jobs, and of course free static sites. You also get automatic zero downtime deploys, health checks and small but handy features like HTTP/2 and automatic HTTP->HTTPS redirects.
It's considerably less expensive as your application scales: a webapp that needs 3GB RAM costs $50/month on Render; on Heroku you'll pay $250/month for 2.5GB RAM, and $500/month for the next tier (14GB RAM).