Not to be worrying is stupidity. Worrying all the time is a paranoia. So the right ratio is somewhat in between.
Realistically, i say 2 things are apparent to me - it seems some people do get batteries unlatching in the air, so one needs to use velcro strap to prevent it.
Second - there was incidents with unexpected forced landings. For that - gps tracker like
marco polo will help to find it, not flying over water will prevent drowning, atti mode switch will help to drive it home. Is it all have to be done? Who knows. I do not think so, and use gps tracker only if outdoors, mostly to cover a possible bird strike or prop brake issue.