Thank you so much for the compliments and the detailed feedback!
I plan on expanding the game further by adding more content (cards and abilities), more game modes (I already have started working on one where you can decide in which slots to place the cards you draw and replace the card that is already in that slot, so the strategy will play an even more role in that) and also add options for the amount of draws of each run to allow the player to go for a quick run or a longer, more strategic one. I agree that a mobile version of the game would be nice too (with properly working tooltips obviously), so I'll probably also consider porting the game there in the future.
As for the cost of shop items, it increases when you refresh/level-up the shop, so the more you refresh, the more items cost, but you are right, abilities' costs need a rebalancing since some are really really expensive (I only had time to balance the cost of simple cards, I didn't really have that much time to balance the cost of ability cards instead...).
Lastly, as for "useless" cards, cards like a "=0" become actually very powerful if combined with some abilities (there is an ability that transforms every "-X" points slot into a "+X * N" points, so if you use a "=0", it means you are basically multiplying points by the corresponding ability's amount. The same goes for possible synergies with the "Areca Nut 0" ability, which synergizes with other cards.
P.S:: congrats on your high score, I don't even know if I ever reached that score myself without cheating with developer controls :o
