Hi!  This is really up to you.  My personal feelings are that I like my chickens to be able to free range, because they're happier hens.  There is always risk when you free range.   With me, it's hawks.  I think that it's just got to be soooo boring for hens to just pace in a chicken run all day.   
So really,  you've got to decide this for yourself.  You can play it safe and keep them locked in a coop with an attached run, or you can let them free range, and just make sure they're locked up at night.
I live in the country with woods surrounding my place.  This will be my third summer with laying hens, and I've lost one per year.  Usually it's a younger pullet or rooster.  They do learn to hide from predators, but they don't always notice in time.....
Good luck to you in your decision.....
Sharon