Challenges were added in the new patch, thanks for the suggestion!
Grid enhancement is something I’ve thought about quite a bit, but I’ve left it on the side for now while I focus on fixing and improving other parts of the game. It’s definitely noted though.
I can’t say for sure yet if I’ll add it, since it could drastically change how the game plays and how certain card effects are designed. As more cards and mechanics get added, I think it’ll become much easier to judge whether expanding the grid would actually improve the game.