The prudent approach would be if you have no plans to use the exterior lights would be to disconnect the wiring, reset the CB, or label it as a spare,and cap off or remove any dead wiring.

This thread helps illustrate how difficult it is to troubleshoot issues like this. Try to explain to a layperson what a professional can see right away.

Not sure if it has been mentioned, perhaps the pump should be on it's own circuit, to isolate it from other problems.

That's one reason I posted. I've successfully done electrical work before. So I'm not a complete novice. But, it took me days of trying to trouble shoot and John fixed it in less than an hour.