You've got a lot to look forward to with your entrance to the world of chickeneering!
I think there are a lot of good reasons to get a rooster to go with your hens, but protection from and defense against predators are not some of them. I like having roosters because they're so handsome, and I think they make a more balanced chicken society, and they fertilize the eggs.
They can also be good at watching out for predators and signaling the alarm. But in my opinion, they cannot be relied upon to attack & defend the hens. They're often the first ones getting out of harm's way. Certainly there are a few self-sacrificing individuals who get their stories told here, but I think they're the exception rather than the rule. Few roos that I know would give their lives to defend their hens, instead, they seem to feel they can better serve the species by keeping their DNA alive & intact, ready to join with that of every available hen.
Look in the coops section for tips on reliable ways to predator-proof your new coop & pens, find out what kinds of critters are most prevalant in your area and build to protect your birds from them. Get a rooster if you want to, he might offer a bit of help, but is not to be relied upon.