Would prevent 'reach thrus'...
...but the tarp on top may be a weak point.
Needs to have wire(or something) under it both to keep critters out and make sure it's supported well enough to shed rain.
Sounds like a good plan.
Keeping chickens is cheep, housing them is not.
I sold some stuff to afford my coop, but I only the bottom 2' of my run has HC, just to keep chicks and bedding contained.
Not sure exactly what you're concerns are but....
If coop is raised you're not losing any run space inside run,
but it may be hard for you to access coop openings.
Another concern is height of run vs coop and covering run to protect from predators.
Is tha close?
Not sure where you plan to put...