Off topic a moment, but you're located just about next door to where I grew up (Northumberland, PA).
Your roo is doing exactly what he's programmed to do, and he's not going to change his programming. You can change how his programming perceives you, though. Like sourland said, don't give in to him or act like he wants you to act (which is like a chicken). You're not a chicken, nor are you a threat or a rival to him, but he's assuming you're at least one (or more) of those things.
Start approaching him with his favorite treats. In fact, always have some chicken-friendly snacks on you when you go out to visit the chickens and offer him the snacks first. Roosters don't give other roosters food/treats. Also, be careful as to how you approach. You're huge compared to him and no rooster likes to be looked down upon or having something leaning over them. So squat down a few feet away from everyone and offer your snacks so you're not imposing.
If he shows you aggression, DON'T give it back. That's what he's expecting; a fight. Instead, do what you need to to move away from him, but do it slowly. You definitely should handle and pick him up from time to time, but at your leisure (not his) and without chasing him all over the place first. If you need to use a net to catch him, fine, but be swift and don't put on a chase.
Also, start spending time in and around your flock regularly. He needs to get used to the fact that you're there to stay and are a harmless feed dispenser and care taker, not a weird looking chicken that he needs to fold into the flock. Above all, be patient. He'll never be the huggable, feather butt he was, but he can be a good roo that watches his flock and doesn't flog you.
Yes, it'd be easier to just get rid of him, but personally, I prefer a challenge.