If you want lots of band options, then the stainless steel model is the most versatile watch. If you don't care for the leather or metal bands, then the silver aluminum band is the second most versatile.
The black steel watch is somewhat versatile with 2 metal bands, a sport band, and a nylon band available for it. Why Apple doesn't make a leather band for the space black watch, I don't understand.
I'm ok with the black watch only having one band color option. I find the solid black look to be very sleek, but a leather option is sorely needed.
The worst ones are the gold and Rose gold options. You get the band Apple bundles for you and nothing more.