I've had several roos that were aggressive and two that were not. The one I have right now, (pictured in my profile) is a Blue Wyandotte that I hand-raised. He's so tame I didn't realize he was a roo until he was more than half grown. Those big feet kinda gave him away then.
I'm gonna say it depends on the breed, how you raise it, and the individual bird, all three. My first roo was a mix breed, he was quite tame and a wonderful boy but really loud. So loud I finally had to rehome him to another chicken keeper with a flock far away from their house so the all hours crowing didn't keep anyone awake. I've tried Orpington, Astrolorp, Barred Rock, RIR and now the Wyandotte and had all but the Wyandotte turn aggressive at maturity.
Master Fluffybutt has been a dream rooster, quiet, gentle, very good to his hens and never aggressive to me. I'm no expert at raising chickens so I make all kinds of mistakes in handling but he's been one patient good bird.