Very good question Joe. It really is a matter of opinion.
My opinion says Hickory, Apple, Cherry, Oak, Adler and Pecan are all good choices. Personally I use a combination of Pecan and Apple for butts, Cherry and Apple for ribs, Hickory and Apple for chicken and Oak for beef.
I do have to order most of my flavors off the internet because locally the only thing available is Hickory and Mesquite.
If you can find it or get some Cherry and Apple try combinations of both with a little Hickory that you now have. Most any of the fruit woods have a sweeter flavor to them that will offset the overpowering Hickory and create a nice combination.
Randy