If you have a large enough tank, I also recommend an Achilies. Mellow tankmates.
Just ensure you use a good QT procedure before adding to your tank. This not only helps with any ailments, but with getting your new addition used to what you will be feeding it, without having to worry about it struggling with food competitions right off the bat as well.
Very mellow, or as mellow as a Kole can be, at first then he went nuts in about 3 months. I've heard some are really good and others aren't. Mine had to go especially with all my anthias.
I have a Naso, Yellow and a Blue "Hippo" that have been happy for over three years now. Most any Tang wont be as mellow as your Naso but many will get along if you have room and introduce them in proper order.