I don't think you'll find anything new that compares to the Kappa 9's for under 5K. You do have the power to drive Apogees/Analysis or Maggies which will be smoother but still prefer to be fairly loud. Neither has the bass you're used to and might require sub. The room is plenty big.
My humble suggestion is to set your sights, budget and patience a bit higher. I went from Kappa 8's to Genesis 350's and never looked back.
My humble suggestion is to set your sights, budget and patience a bit higher. I went from Kappa 8's to Genesis 350's and never looked back.