I know there are many who will disagree with me, but you should never have to put up with an obnoxious rooster lunging at you! You poor thing

Roosters are a dime a dozen, and unless your roo is an extremely rare, seen practically nowhere else in the world, and he is a sport roo, or can play the Star Spangled Banner on a guitar - - - he'd be Christmas dinner.
Have you tried carrying him upside down to show him who is boss? It doesn't hurt them at all when done properly; it only hurts their egos. Doing it repeatedly has brought about the desired effect for many people on this forum.
In regard to the raw red patch I'm leaning more toward buggies than anything else (mites in particular but could be lice). It's nothing you have done or haven't done, mites are easy for chickens to come in contact with...birds in your area mainly (such as robins, crows, etc) any sort of wild bird can carry them around.
I'd also check for lesions (they'll look like that really horrible nasty pimple you had in high school that simply wouldn't pop, but had no trouble getting infected)...feather loss can be an early sign of avian pox, but I don't think that's what they have.
Have you changed anything at all in their diet lately? What is the percentage of protein in their feed? Plant protein versus animal protein?