the passenger
I donīt think flying is unsafe but I hate tendencies to decrease the safety margins, even if it is only by a very small amount.
Have you considered the impact on safety margins of an airborne return?
Flying such a long route over water
If you read the comments by the professionals on the forum, the LAX-LHR is not a long over water route.
I have flown 100km over water in a single engined aeroplane (when I was younger) - that makes me nervous when I think of it now, but the 3 engined 747 does not in this incident, remember that it is certified for NORMAL operations on three engines, due to the high levels of redundant systems.