Are you looking for playing card games with the standard deck of 52, or other games as well?

Rook uses a custom deck with 57 cards, four colored suits of 1-14 plus a wild Rook, but versions using it are fairly similar to many traditional acts games with standard playing cards.

Phase 10 is a rummy-like game with a deck of 4 colored suits from 1-12, 2 copies of each number for 96 total cards, plus 8 wild cards and 4 skip cards.

Pinochle might be a challenging game to program since it has more complex points and tracking systems while still using standard cards. No new art required.