My concern was simply that 9 money cards per player (at 4p) might not be enough for the game’s 10 auctions, especially given that the game eats money cards when you don’t win something. But it would be easy enough to try it and see.
I think it makes sense to try it with the basic deck.
As a general rule of thumb, I try to leave the extended deck cards out of Decktet games unless there's an obvious use for them. They're an extra resource to use if there are problems with a game that need to be solved, rather than something that must be shoe-horned in.