At 6 months roosters can become a handful as their hormones kick in and they start trying to figure out what dangers they need to protect against.
The wing flapping thing is posturing or trying to get attention. It's not anything to worry about unless he's trying to beat you with his wings. That's called "flogging" and that's aggressive.
If they waggle their heads or do what I call the "death metal growl" (it's a croaky sound like "rrrrrrooooowrrr") he's expressing annoyance or he thinks there's danger.
Raised hackles is a direct challenge and a prelude to an attack.
You need to put a stop to the chasing and herding and pecking behavior. Some people favor some rather dramatic measures, I prefer something more subtle.
I'll stand my ground with my hands on my hips and shake my head (mimicking the "I'm annoyed" head shake). Sometimes the roo will try a "chest bump" to get you to move. Don't. If he starts to peck at you shoe give him a push with your foot to get him out of your personal space. Never bend down to to use your hand because that brings your eyes within beak range and roosters at this age have zero impulse control.
If you're walking and and he makes runs at you from behind, don't let him think he's making you run away. You never want poultry to get the idea they can push you around: they're absolutely ruthless bullies to any creatures they regard as weaklings.
The trick I go for is to establish that he can't push me around without escalating the aggression. If you get a hard peck, push him out of your personal space though. I'm more firm with those if I get nailed when I'm kneeling or bending over, as again I don't won't them getting pecky when my face is that much closer to them . I have rarely had to do that more than once.
Also, I really wouldn't ever let a chicken roost on my shoulder, especially if you have any earrings or other jewelry on your head or face. Chickens have poor impulse control with shiny things.
If he starts trying to spur you or jumps at your face, all bets are off and and you need to either cull or re-home him.