re: What is your go to rub?

It sucks that your wife can't handle cayenne, OP. I love it. I doubt it would work trying to explain to her that the burn is an illusion and how she could develop a tolerance. Even on a nice steak that really only needs salt & pepper I sometimes can't resist the urge to sprinkle on some cayenne.

I've been developing my own rub over the years. Here's where I'm at now: I haven't really mastered a salt-to-spice ratio so I add them separately. I start by applying a layer of mustard powder. I apply it fairly liberally. Then I apply the salt & pepper appropriate for the size and type of pork (I've never done this for beef or chicken). Then I apply a rub that is mostly chipotle but with smoked paprika, cayenne, crushed dried habanero, onion powder, and sugar to balance the heat -- turbinado for sure but maybe also some brown sugar if I have it on hand. The chipotle is the star.

I've stopped using ancho. I like chipotle a lot better. I used to always use garlic powder. I love garlic. But I usually have it in at least one of my sides so I cut it from my rub and haven't missed it. I've cut out cumin, coriander, and fennel.

I'm not sure where I stand on aromatic herbs, I've used them with varying success. Since I'm really only using a rub on meat I'm smoking for hours, it seems out of place. Of course I'll always use Rosemary if I'm smoking lamb but for ribs or a pork butt I haven't used any in a while. I've made rubs in the past that benefitted from aromatic herbs so maybe I'll experiment more in the future. I love thyme and perhaps a little sage would fit. But that's where I'm at on my journey right now.