I'm sold. If I can find each color option, maybe I'd do them exclusively.
Do you suppose it's best to wait until spring to start the flock at this point?

I'd wait til spring. It's rather late in the year for chicks, and you get 10 more months of time to prepare and research your chosen breed. Or maybe it's just OCD me that does that.

Either way.... If you get chicks after August, you might well end up with frostbite trouble all winter. I did---last year I hatched August 22 and they ended up getting frostbite bad enough one nearly died and the other one would have if she hadn't been indoors for cocci treatment.