1. Buyable packs: You can buy a pack of cards for the price of a 100 tickets, after round like 5, they seem useless.
2. Possible card remake: Just redraw all the art for cards, have it a setting to change it from the new or the old art.
3. More special cards: the special cards seem a bit bland, I suggest you add more.
4. Items: just so that tickets are more useful and is for the pressure of the game, increase the price for items after every round, you could also add more
Item idea 1: "Acidic drink" digestion has a 5% chance to double its power when the pred has less than half of their stomach full. Price: 150 tickets
Special card idea 1: "Long term digestion" have all preys inside a pred's stomach become undigested for 3 rounds (starting when you use it) after the three rounds, double their points (pred would be unable to eat when used)
Pred idea 1: Pred copies a random prey inside stomach onto the tables (only once per round) Stats: 4 or 5 energy, 2 digestion, 1 capacity (favorited: +1 digestion but levels are 10% harder)
Item idea 2: "Controller" produces either a table reroll or a deck reroll after every round. Cost: 170 tickets
Item idea 3: "Copy machine" gives 5 extra points for each same type of prey is inside a pred but only starts at the fifth copy
(Would edit this later for more additions but my mind is blank rn)