My only clarification here is your braking setup. If you are going with rim brakes, the Nexus should be fine. If you have the capability for a disc brake, consider the alfine instead of the Nexus.
If you are opting for the internal brake, I'd highly recommend the most bulletproof tires you can get (marathon, armadillo, gatorskin, etc) because flats are a real pain with the internal brake.