Adding observability to a system is a good start. Being able to see what is going on is just the start.
Now that you have the data you can start cleaning up errors. Look at the logs and try to clear the most frequent errors. Statistics determine that at any given time a few errors will dominate. Try and add details to break them down into categories.
Once the backgtound errors are out the way it is much easier to see the impact of any incident or change.
Look for any gaps in the information you have. Is sonething not instrumented?
Observability gives you the information that you need to make data driven decisions about your systems. It is almost a conversation where you can ask where is it wrong.