I'd say the best option is just to say something like "you don't like having hair in your mouth right? It's the same for a guy" - ie, explain it to her in a way she understands. I'd think any reasonable chick would give it a shot, unless she didn't actually like you or something. But you said you've been married for 18 years, so that's probably not the case.
"bitch, relationships are about compromise"
I'd agree with the waxing, never been with a waxed chick, but wow that would probably be pretty cool, they always tend to look the best, and unless the shave is like really recent, it's really stubbly and sharp, I've actually came up with like small scrapes and such after goin' to town...
I used to think it was kind of odd for a chick to be fully shaven, but I've come to appreciate it more, if the chick knows what she's doing, you're not gonna feel like you're a pedo...lol.