I think Dolch is a pretty good candidate for a first run, since it's a pretty well-established set that people like, and there just isn't a complete authentic ANSI set available owing to the layout.
One thing I was really interested in that I don't recall being asked in this thread: is it going to be possible to have Cherry profile space bars but with center stems to fit modern boards? How about stepped Cherry caps locks with centered stems? Those two would be great alongside a Dolch set if it could be done, perhaps have the sets include both the centered and off-centered version; not sure how that would play out exactly or if it's something GMK would be willing to produce. Maybe that could come later on.
Also, if not Dolch, perhaps something similar but a little darker, more graphite-themed, as others mentioned.