Hi!
Sounds like you have some good ideas. I'm working on pied projects myself And have planned out super pastel pieds, banana pied, enchi pieds, fire pieds and my long term goal is some double recessive albino pieds. Really it's up to you, what you prefer to see when you open your tubs everyday. From the ideas you gave, I say you are on the right track!
As far as spieds go, I don't particularly like them, but that's just me. Some people prefer high white pieds, some prefer low white. I'm actually right in the middle, I prefer a nice even distribution of color and white. So when it comes to selling them, it's really down to how big the market in your area is for spieds, how well you market your snakes and if you like spieds yourself, because you may end up keeping some long term before they sell.
Good luck with everything!