Having had to use the point in time restore feature before, it's indispensable.
Just taken a look at Appliku as others have mentioned it (we are a Django app), that on DigitalOcean with their managed Postgres could be a strong option.
If I were looking for "very good Postgres", I would go straight to Crunchy Bridge. I don't think a PaaS is going to get anywhere near that level soon (and I work on Fly.io, so I know we're not).
Building a good PaaS and building an amazing managed database service are two problems that overlap less than you think. The moment we can get Crunchy Bridge or someone at a similar level to run their DBs on our infrastructure is the moment we start using them for customer Postgres.
No one knows this yet, but we have managed Redis soft launched in our CLI. Fly + Upstash is a pretty good combo.
(I have used neither Crunchy Bridge nor Amazon RDS, so this is an actual question, not a challenge! I have used Heroku postgres as well as self-hosted postgres)
Another big area is tooling we're building in to help app developers. Things like health reports for your database, built-in audit logs, simple SSO integration are just a few things that you now don't really have to think but can benefit heavily from. Overall we're a pretty big parallel to Heroku Postgres, with more to come (I wrote about some of that vision here - https://www.craigkerstiens.com/2022/05/18/unfinished-busines...).
There is a heroku config vars sync, so you can keep using Heroku Postgres, but moving the app itself out of there.
Your vars will be in sync, so when heroku rotates credentials they will be quickly applied to your app deployed with Appliku