As with so much in life it is a case of picking one's battles and picking one's risks.
I am happy to fly over the Alps above a solid overcast, but the exposure is only about 30-45 mins and happens barely a few times per year, and is less than 1% of my airborne time.
The risk is further improved by the fact that one is flying at a very low power setting (a non turbo engine) so the stress on everything is a lot lower than during any preceeding climb and lower altitude flight.
And maintenance needs to be done on a money-no-object basis, with a zero tolerance for defects. If the engine as much as coughed on a flight, I would have the fuel system inspected and would probably replace the fuel servo as a precaution, before further flight. This is why I do not fly other aircraft.
But if I was doing flying which has no decent escape route all day every day then I would probably take a 737
Same with flying at night. I do it but only here and there. Night time is just 1.5% of my day time. Night flight is the most worrying for me because there really is no escape route - short of wearing NVGs
The problem with a piston twin is that one pays heavily on the hourly operating cost for the spare motor, and the only "modern" option - a DA42 - has a couple of engines which are thoroughly proven to be dodgy. Practically everybody I know who has a DA42 has had so many problems with it that I simply wouldn't do the long trips I do.