you you have an old panel, consider a replacement anyway. My son is a Master Electrician. He regularly replaces Federal Pacific panels that are in recall.
https://safeandsoundelectric.com/2021/03/17/the-hazards-of-federal-pacific-electrical-panels/
Also, you can add an another panel to your service, for a garage, etc.
Not an issue...if your home is 20+ years old you probably need to replace the panel.
Also, walk around your house and place your hand on the outside of each plug outlet (wall) and on each switch outlet. If they are warm, replace them before the fire starts.
Great idea! And I’ve got a laser heat gun so that will be easy.