Hi Becky
I'm truly enjoying reading your threads/posts!
I go for a pretty face, don't care how many buds it gets if it's not pretty
Plant habit would be next, I have some that tend to multiply in a straight line instead of a clump.
More and more I'm starting to like tall plants that can be at the back of the garden/bed and am wanting to acquire more late season cultivars so when everything else is done blooming there is still some color.
In regards to you question about fragrance, looked at the AHS database, there are 20,728 registered fragrant cultivars and 2,403 very fragrant registered cultivars. You might want to take a look-go under advanced search.
-Sandy