I don't speak for everyone, but here are my thoughts on this:
But what do you plan to DO with this?
If this works out, it could lead to a lot of things, but I see the immediate goals to be (1) promoting Tapas in general and (2) getting us accustomed to large collaborations.
Post all the cards for free online for folks to just, look at, or actually get it printed in a deck? What would you do with the deck; kickstart it? send one to each of the creators only? sell them freely online?
I feel that we should start as small as possible, and that producing 78 illustrations is enough challenge for the moment. Let's aim for a version that people can print on their own.
Making people print out their own card decks is a little labor-intensive, but it has the advantage of not costing us anything.
Of course, we could be pleasantly surprised and end up with a professional-quality Tarot deck. In which case we'll have to look into a limited print run, or maybe a licensing deal with US Games.
If so, who gets the money for it? Do the artists get paid a tiny percentage each or would you pool the profits for an agreed upon charity?
Divided among this many artists, the profits aren't likely to amount to much, so the money should probably go toward promoting Tapas, promoting the artists as a group, promoting Tarot cards in order to lay the groundwork for future collaborations, or a combination of all three.
Just imagine: The 2018 Tapas Tarot; followed by the 2019 Tapas Tarot; followed by the 2020 Tapas Fantasy Tarot, the 2020 Tapas Romance Tarot, the 2020 Tapas Horror Tarot . . .
Is there going to be a collective "style" we would need to follow? Like a type of background or inking style?
These may be able to wait until after the proof-of-concept deck, but the card backs will definitely need some standard artwork.