The bathroom is generally the worst place to put a first aid kit. But I guess you knew that
My main kit is in a box in a low kitchen cupboard, and is generally accessible. I happened to need some tweezers from it the other day, so I know it hadn't got buried under other junk or anything. It's full, because I very rarely need it. No children in this house.
There are a few pills, bottles and plasters loose in another cupboard above it. That doesn't get used much either, but I might need a headache tablet 3 or 4 times a year.
I have a kit in the boot of the car, and a smaller kit in a waist-pack that I usually have with me when I'm away from the house. Also, I keep a few pieces in my pockets.