Rib roasts (prime is a grade of meat...most grocery stores are choice rib) this alone can make a big difference in taste. Unfortunately rib roasts just don't have the best flavor internally.
I have done them pretty much every way you can think of. Kosher salt crust is one of my favs. Smoked is prolly my least fav.
Last year I tried for a better herb crust, butter rub with heavy salt/pepper/garlic/herbs in that order, then let sit at room temp for 24 hours before oven cooking (theory of a kind of dry aged experiment) sketchy letting a $100 chunk o meat sit out of fridge that long

. Turned out really good!!
Last night did a new idea to me, like BB ribs, yellow mustard rub, then HEAVY seasonings.

This one may have knocked the salt crust from the top! For the center cuts You can take some of the crust off the fat cap area and sprinkle em on the center red meat.
Not a big fan of horseradish on rib roasts (I like the beef to taste like beef) but every once in awhile its ok. next time I will try to do a HR cream rub, then the spicing's.
PS, got this one just a touch to done, but still MR