May have to contact Rob about making somethign similar for me!
Yes, I tend to like the proportions of the 38mm Spirit Pioneer a bit better, but it's hard to know for sure without seeing it in the metal. The Mark I has an entirely different presence on the wrist than it does in pics. (More so than most watches in my experience).
I find the 38mm in this dial design looks far smaller than my 38mm Serpent Calendar... mostly because of the chapter ring design, I think, and also maybe the black dial contributes to it as well.