UPDATE: looks like the $2499 GFX50S cameras sold out in an hour or two. Don’t feel bad—there are bundles with lenses that end up pretty similarly priced with the GFX50S II—Fujfilm has not been discounting its lenses for some time now.
Looks like Fujifilm wants to clear out older models.
The “II” model is $1500 more, and the key advantages for it are in-body image stabilization and being more compact and lighter weight. But its EVF setup is built-in and fixed in place, unlike the original.
The $1500 savings goes a long way towards a lens. My recommendation for the best all-arounder is the Fujifilm GF 50mm f/3.5, equivalent to about a ~38mm lens on 35mm format.
Important to my B&H loaner support — buy your gear via links on this site.