I know that this does not directly address your question, but I thought it might help, being that re-homing an adult cat can be difficult. We had a cat who was fairly aggressive, and even though I've had cats my whole life, I didn't think there was anything I could do about her "claws out" behavior. My husband, who has always had dogs, told me he was going to train the cat not to act aggressively toward us. I thought he was crazy, and told him so. Well, I'm here to tell you, he did it. His methods were unconventional, but they worked. Our cat would slash at us all the time, and hiss. Every time she did that, he sprayed her with water (he literally carried a spray bottle with him everywhere in the house). Cats hate that. She came to associate hissing/slashing with immediately getting sprayed with water, and within about 2 weeks, she had completely stopped her behavior. Additionally, I kept her claws very short. We trimmed them frequently so they were not long and sharp. (Now they have those little claw things that you can put over the cat's claws, which is a good idea too.) You can also get toys that are good for high-energy cats (we have one that is basically a feather on a piece of elastic cord, tied to a stick - kind of like a fishing pole, and we also have a laser pointer thing). The kids play with our crazy kitty using those toys so the kids are safe, and the cat gets exercise without hurting anyone.
If your kitty is otherwise sociable (sounds like he is), you might just try behavior modification with him. He might be a totally different cat within a few weeks.