OldSalt92,
What specifically about safety is she concerned with? Is it visibility, front end collisions, fire hazards, escape routes?
Are you looking to purchase a new rig or used? My original plan was to get 20+ years out of our rig, which will bring me into retirement age. We're on target to do just that. Then purchase a nice, used, high-end coach about the same vintage as our current rig, depending upon the actual make & model, but I'm planning in the $100K range...maybe a bit higher. Depending upon your budget, you might be able to do the same with either a C or an A.
I have a gasser Class A, and at times the noise can be a bit much, but that's just under hard acceleration or steep grades. The rest of the time, it's not that bad. Of course, not as quiet as a rear-engine motorhome. I would think that the quietest option for the passengers upfront is a DP class A.
By the way, I ordered our Class A with a driver's door, which I use quite a bit. I know it's a rarity on the larger Class A's, but I'm wondering if it still might be an option with some manufacturer's if you order new. If I remember right, it was a $400 option for us back in 2004.
Good Luck in your search,
~Rick