Welcome to the mayhem.
I was going to say ask away, but broggy beat me to it. To your questions.
I haven't noticed any rattling on mine unless the bumps were pretty large or sharp. It seems quieter than the last 3 very respectable tourers I had, so perhaps you are hitting some big potholes or it just is a loud one that needs some tightening up, or just aren't used to hearing one with a lot of plasic, hard to say.
The front suspension. Well after a Goldwing it was a pleasure. Honda seems to make the suspension soft and then put anti dive vales in some of them to stop the front from overloading in a stop. Not sure how the Shadow plays in to the equation.
The suspension seems to me to be tuned well for the bike. I guess there could have been a mechanical fault to what you felt but would lean to it isn't what you are used to.
Make sure your suspension is set properly for you long 2-up test ride. Err on the side of being heavy. After some time on it you'll appreciate the suspension (like in those twisties you talked about) and the adjustable rear will make momma happy, so will the luggage space and weight rating. She can carry "stuff" on a trip. LOL
Some people go their whole life wondering if they made a difference, Marines don't have that problem.~ Ronald Reagan
2012 XCT, AFR+ Gen 4, Lloydz air filter. I don't equate noise with power.
I ride with the Force.