Hey, James! Congrats on the new family member!
My wife and I had birds for a long time, including a blue & gold. They are very interesting to have in the house, that's for sure. Since you've already heard a squawk, at least the first one won't be a surprise. You're right about the volume, though, you can hear one in the wild a mile away. When he decides to let one go 5' from your head while you're watching TV, he will get your attention.
Adult birds can either bond immediately with a human that they just take a liking to, or they can decide they hate you right from the first look. If a previous owner who happened to wear glasses abused him, and you wear glasses, that's not a good start. He apparently took a liking to your wife, and that's great for both of them. If he didn't draw blood with you and just left a mark, then it was just a gentle warning, so the two of you will probably be fine after he gets to trust you a bit more. Give it time. Be around him, speak softly, just sit quietly in his presence, and his curiosity will eventually take over.
The biggest impact on your daily life will focus on cleaning, and I'm not talking about the bottom of the cage. As you probably know, large parrots have a dusty powder on their feathers, and when they flap their wings for exercise, it eventually settles everywhere. Also, just like you leave hair around the bathroom floor, they leave little feathers. And then they flap their wings just for the fun of it...have I mentioned that they have large, powerful wings?...and then the little feathers go everywhere. He will be eating lots of different kinds of seeds, and he'll drop the hulls and skins to the bottom of the cage when he eats. Have I mentioned they like to flap their wings...?
His wings will be clipped of course, so he won't be flying around the house. Macaws love to climb, so he'll love to climb around the outside of his cage and sit on top. Oh, you haven't mentioned the cage. You MUST have a cage designed for a bird as strong as a macaw, or he will break the wires when he chews. Just like any parrot, they love to chew and bite, both for the exercise and to keep the beak from growing out of control. The cage must be large, and it must be strong. An acquaintance had a hyacinth macaw, and put it in a cage that was intended for a large parrot, but not for a bird as strong as a hyacinth. The bird systematically went around the top of his cage, snapping every other weld on the vertical pieces of metal where they joined at the top. Just because he could. For the fun of it.
Also, as I know you know, birds go to the bathroom whenever and wherever the urge strikes. And, as I've mentioned, they love to climb around the inside and outside of the cage. So, when they're climbing up the inside of the cage, the business end is pointing "outside", and when he goes, that's where it goes. They are very large birds. So, walls are cleanable, but you can't have anything upholstered within two or three feet of the cage, and I would strongly recommend something like a plastic sheet or tarp under the cage that extends several feet in diameter away from the cage. You've been warned. Lay a towel across your shoulder before you let him sit on you.
If you haven't done so yet, you need to find a veterinarian that works with large birds. You can't take a macaw to just any vet. It's better to have a vet already set up, including a first checkup for your bird, rather than to wait for an emergency and then start looking.
Birds the size of a macaw are quite intelligent, and can outlive you. He will definitely become one of the family. He'll look forward to you coming home from work, and he'll look forward to attention and interacting with you and your wife. It's going to be a lot of fun!
