I don't mind Hallertau in my Belgians if I've got some around, but if you're looking to buy more anyways I'd say Saaz is probably the hop I use the most in my Belgians. For the pales, it depends if you are talking english or american pales. For English, something like EKG should get used quite a bit. American could use any number of american hops (centennial, cascade, amarillo, citra, etc.).