I can list several major problems I created that took many months to solve that make me look incompetent.
So I'm the pot calling the kettle black.
Also: hindsight is 20/20.
However, I have to disagree in one aspect, it is not basic electrical engineering practice to add filter capacitors on every node. Some nodes need it, some don't. This one, by the topology of the circuit didn't, but from the need for immunity did. This is not always obvious, but for sure I could have anticipated.
Hindsight is definitely 20/20 on this one.
If you think this way, you are already on a good path. Think that there's a lot of folks that don't even care at all, you do care and want to improve, that sets you apart.