In my opinion it's Type-F

Because:
* It's bi-directional
* It's grounded and ungrounded plugs use the same socket
* It's already widespread
* Your fingers can't touch the live wire as you're plugging in a wire
* Low footprint

What’s the difference of C and F type?

C is mostly for low power devices

F is basically a heavy duty upgrade of C, it's got grounding on the side can handle 16A (ovens, heaters etc.)

Don’t you get numpties plugging F appliances into C sockets then complaining to customer service that the induction stovetop doesn’t boil water for tea fast enough?

You cant the plug is thicker