Howdy, and welcome indeed! I've been cruising these forums for well over 5 years, and am still addicted! Good people and good advice.
Now, the thing about mufflers is that they don't HAVE to be loud to get you what you're looking for. The real advantages to good quality high-flow mufflers is increases in gas mileage and power. Flowmaster makes high quality stuff that works, and the good news is that not all of Flowmaster's products are annoyingly loud! Go to their website and check it out. If you were to get a 50 series Delta Flow model, it wouldn't really be all that much louder, especially in the cabin. Outside it would sound nice, but nothing like all the cheap "ricemobile" Hondas you see everywhere.
Also, a note on deliberations with your wife: Show her the real world advantages to a purchase of a new muffler. She probably is going to instantly think of that annoying teenager that lives down the street who drives the car with the obnoxiously loud muffler the size of a milk jug hanging off its bumper, but just let her know that a good quality muffler doesn't sound like that, and it will give you better gas mileage, saving you literally hundreds of dollars on gas every year! It pays for itself in as little as six months, and it will increase the resale value of the car.
See where I'm going with this? I'm married as well, and am beginning to gain an understanding of the female mind. She just needs to know that this isn't a superfluous purchase of another toy, but rather it is an investment that will increase the quality of life for your family.
You're welcome.