They're pretty well protected in that position
Over the years I've had probably a dozen hella lights break off at the base, but my vehicles get seriously abused compared to what most people would do.
As an indication, I've had 3 vehicles snap chassis in the same period of time!
The switch on the back is kinda useful in some ways, but I tend to prefer a dash mounted switch, as I've seen jokers go round switching work lights on in pub carparks! My rear light(s) usually switch using a relay off of the revers light as well, as I tend to do a lot of "precision" reversing at night (lining up on drill rigs/holes) and its not appreciated reversing over an offsider!
A lot of campers who have swing away style spare wheels have a telescoping pole mounted behind the wheel, with a curly lead to the light. They higher you can get the light to set up camp the better spread you get and the less its in your eyes. Haveing a piece of pipe next to the light for the curly cord to curl back up into at the lower position stops it flapping around. I don't have any pictures, but I'll try draw it in MS Paint
Sean