Your application is a complex one. The questions are, what do you need it to do, and how easily/cheaply can that be done? For newbies, half the battle is learning what you can do with Grafik Eye. Your design will evolve as you do. If you have the time you can continue your learning curve (there's lots more to learn). Or you can hire someone who knows the system's capabilities while you concentrate on defining what you want to accomplish. I'll make some comments for you to consider.
Any suggestions besides this site to continue my learning curve?
That location you "can't get to" with LV? How much you want to bet?
You might end up with a mixed system, and with 9 zones to control you will need at least two GEs. But that's not a difficult design issue since GEs talk to each other and the second one can be made to act as a direct extension of the first.
Do you mean Space and GE mixed, or two GE's?
Walk-through lighting (including the stairway) can be handled in an integrated GE (not Spacer) system by defining a scene that brings up the walk-through zone while leaving the other zones untouched, and another scene that takes the walk-through zone down while leaving the other zones untouched. No need for three- (or four-) way wiring.
There is a vast array of wallstations (switches, keypads) for GE, many two-button. Surely some one of them will satisfy...
Are there more controls than are shown on the Lutron website?
There are also occupancy sensors that will turn on the lights when you enter a zone (e.g. the stairway) without manual action at all.
I didn't see them on the Lutron site. Did I miss something
For various reasons, target the 3500 series rather than the 3100 or 2000 series, if at all possible.
I assume you mean the 3506 vs the 3106, correct?