The shortcuts that must go
Hard-coded configuration, a single environment, manual deploys and no backups are acceptable while you are learning. They are not acceptable once customers depend on the system.
Add observability before features
Logging, error tracking and a handful of alerts are the cheapest insurance available. They also make the next feature faster to build.
Decide what to rewrite
Rewrite the parts you got wrong about the domain. Keep the parts that were merely written quickly — speed is not the same as debt.