> difference between suborbital flight and putting a payload in orbit. What looks like a next logical step actually takes 10X or more effort, scale, and testing.

But suborbital flight and payload in orbit is much less of a difference than you might think.

The delta V is not that significantly different. Scale is almost the same, and a little bit more power and (second stage) your payload is now hurtling around the earth instead of falling like an ballistic missile which was what their suborbital predecessors are.