Sprouts1115: Thank you. I left the closeness between the numbers and spades because it matched the other cards' placements, so when you flip through hearts, spades, diamonds, and clubs are all in the same spot and about the same size. Maybe not everyone would agree with my choice here...
From a practicality standpoint, you generally want the indices to be easily and quickly identified.
But I wouldn't sweat that too hard really - your deck is a bit more whimsical than practical, more about the art, less about poker and the like. When a deck is made as an art deck, many of the traditional conventions of playing cards can be bent or even broken for precisely that reason - it's art first, a pack of playing cards second.
Anyone wanting to play a stone-cold serious card game can pick up a pack of Bicycles or Bees from nearly any big box store or pharmacy chain. This deck isn't for that purpose.
As I see it, there's consistency in design, there's attractive art pieces, there's a common theme - you've got the necessary elements.
The biggest stumbling blocks are the cost and the quality. Art decks do tend to be more expensive, especially if they're made by a collective of artists rather than just one. But it is truly impossible to wrap my head around any deck made by MPC being worth $20 unless one of the cards was printed on a twenty-dollar bill. They do adequate work in print quality but the stock and coating quality isn't there for such a premium price.
Consider shopping for a better printer. Get a price quote from Expert PCC or Legends PCC - both companies have "PCF Agent" accounts here so you can interact with them directly. They both do excellent work and are friendly to work with, unlike the stories I've heard about a certain major card printing near-monopoly that I won't mention here... Make a stretch goal for a better quality deck with a better printer and you might get more than a few nibbles.
And as expensive as the paper decks are, the plastic decks are budget-busters. It might be more practical to cancel anyone who is selecting them as an add-on. The fact that they are just add-ons and not on any tier is good - you can't cancel a tier as long as even one person remains pledged at that tier, though you can lock the tier down and prevent new backers from choosing it.