Did we cover what I should do when he charges or hisses aggressively?
For the hissing, I'd just say "no" in a firm but not loud voice. Immediately after he stops hissing and his body language tells you he has relaxed, throw him a treat once you find one he likes. In the meantime, say "good boy" in a warm and praising tone, continuing the praise when you give him treats. Never treat or praise when his body language or behavior indicates he is anything other than relaxed.
For the charging, try using a towel, blanket, or large piece of cardboard to mask your legs when you see him starting a charge or even when you're walking around your place and you think he may charge. He associates legs with something bad. Hold the towel or whatever on the side of your legs facing the cat. Say "no" firmly; praise and give him a treat those times you walk by and he doesn't charge. Seeing a solid wall, so to speak, instead of the legs that he associates with bad things, may stop the behavior. It will at least redirect the behavior onto something other than you. It's a technique I was taught to use with bobcat & cougar when I was a wildlife rehabilitator.
And when I physically can't hold him anymore, I sit on the couch and he lies on my chest and lap purrin up a storm. BUT, it does take time to get this point (or any other point, lol) with some higher generation babies. He now enjoys being carried around and held MUCH, MUCH more than my DSH's and Maine Coons!!!